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* [PATCH] iio: adc: Replace, rewrite ad7745 from scratch.
@ 2011-09-16 13:12 michael.hennerich
  0 siblings, 0 replies; 6+ messages in thread
From: michael.hennerich @ 2011-09-16 13:12 UTC (permalink / raw)
  To: jic23; +Cc: linux-iio, device-drivers-devel, drivers, Michael Hennerich

From: Michael Hennerich <michael.hennerich@analog.com>

The existing ad7745 driver didn't conform with the IIO spec for such devices.
It was way simpler to rewrite the existing driver, than actually fixing it.

Changes since V1:

Fix file header description.
Fix erroneous defines.
Pin channels to expected places in the iio_chan_spec array, to avoid magic numbers.
Use msleep instead of busy waiting mdelay.
Fix indention style.
Drop _bias and use _offset attribute.

Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
---
 drivers/staging/iio/adc/Kconfig  |    2 +-
 drivers/staging/iio/adc/Makefile |    2 +-
 drivers/staging/iio/adc/ad7745.c |  672 --------------------------------
 drivers/staging/iio/adc/ad7746.c |  801 ++++++++++++++++++++++++++++++++++++++
 drivers/staging/iio/adc/ad7746.h |   29 ++
 5 files changed, 832 insertions(+), 674 deletions(-)
 delete mode 100644 drivers/staging/iio/adc/ad7745.c
 create mode 100644 drivers/staging/iio/adc/ad7746.c
 create mode 100644 drivers/staging/iio/adc/ad7746.h

diff --git a/drivers/staging/iio/adc/Kconfig b/drivers/staging/iio/adc/Kconfig
index 7867ab1..0482073 100644
--- a/drivers/staging/iio/adc/Kconfig
+++ b/drivers/staging/iio/adc/Kconfig
@@ -144,7 +144,7 @@ config AD7793
 	  To compile this driver as a module, choose M here: the
 	  module will be called AD7793.
 
-config AD7745
+config AD7746
 	tristate "Analog Devices AD7745, AD7746 AD7747 capacitive sensor driver"
 	depends on I2C
 	help
diff --git a/drivers/staging/iio/adc/Makefile b/drivers/staging/iio/adc/Makefile
index 990d3fa..5ba3cdb 100644
--- a/drivers/staging/iio/adc/Makefile
+++ b/drivers/staging/iio/adc/Makefile
@@ -33,7 +33,7 @@ obj-$(CONFIG_AD7150) += ad7150.o
 obj-$(CONFIG_AD7152) += ad7152.o
 obj-$(CONFIG_AD7291) += ad7291.o
 obj-$(CONFIG_AD7314) += ad7314.o
-obj-$(CONFIG_AD7745) += ad7745.o
+obj-$(CONFIG_AD7746) += ad7746.o
 obj-$(CONFIG_AD7780) += ad7780.o
 obj-$(CONFIG_AD7793) += ad7793.o
 obj-$(CONFIG_AD7816) += ad7816.o
diff --git a/drivers/staging/iio/adc/ad7745.c b/drivers/staging/iio/adc/ad7745.c
deleted file mode 100644
index 4739593..0000000
--- a/drivers/staging/iio/adc/ad7745.c
+++ /dev/null
@@ -1,672 +0,0 @@
-/*
- * AD774X capacitive sensor driver supporting AD7745/6/7
- *
- * Copyright 2010 Analog Devices Inc.
- *
- * Licensed under the GPL-2 or later.
- */
-
-#include <linux/interrupt.h>
-#include <linux/gpio.h>
-#include <linux/device.h>
-#include <linux/kernel.h>
-#include <linux/slab.h>
-#include <linux/sysfs.h>
-#include <linux/list.h>
-#include <linux/i2c.h>
-
-#include "../iio.h"
-#include "../sysfs.h"
-
-/*
- * AD774X registers definition
- */
-
-#define AD774X_STATUS		0
-#define AD774X_STATUS_RDY	(1 << 2)
-#define AD774X_STATUS_RDYVT	(1 << 1)
-#define AD774X_STATUS_RDYCAP	(1 << 0)
-#define AD774X_CAP_DATA_HIGH	1
-#define AD774X_CAP_DATA_MID	2
-#define AD774X_CAP_DATA_LOW	3
-#define AD774X_VT_DATA_HIGH	4
-#define AD774X_VT_DATA_MID	5
-#define AD774X_VT_DATA_LOW	6
-#define AD774X_CAP_SETUP	7
-#define AD774X_VT_SETUP		8
-#define AD774X_EXEC_SETUP	9
-#define AD774X_CFG		10
-#define AD774X_CAPDACA		11
-#define AD774X_CAPDACB		12
-#define AD774X_CAPDAC_EN	(1 << 7)
-#define AD774X_CAP_OFFH		13
-#define AD774X_CAP_OFFL		14
-#define AD774X_CAP_GAINH	15
-#define AD774X_CAP_GAINL	16
-#define AD774X_VOLT_GAINH	17
-#define AD774X_VOLT_GAINL	18
-
-#define AD774X_MAX_CONV_MODE	6
-
-/*
- * struct ad774x_chip_info - chip specifc information
- */
-
-struct ad774x_chip_info {
-	struct i2c_client *client;
-	bool inter;
-	u16 cap_offs;                   /* Capacitive offset */
-	u16 cap_gain;                   /* Capacitive gain calibration */
-	u16 volt_gain;                  /* Voltage gain calibration */
-	u8  cap_setup;
-	u8  vt_setup;
-	u8  exec_setup;
-
-	char *conversion_mode;
-};
-
-struct ad774x_conversion_mode {
-	char *name;
-	u8 reg_cfg;
-};
-
-static struct ad774x_conversion_mode
-ad774x_conv_mode_table[AD774X_MAX_CONV_MODE] = {
-	{ "idle", 0 },
-	{ "continuous-conversion", 1 },
-	{ "single-conversion", 2 },
-	{ "power-down", 3 },
-	{ "offset-calibration", 5 },
-	{ "gain-calibration", 6 },
-};
-
-/*
- * ad774x register access by I2C
- */
-
-static int ad774x_i2c_read(struct ad774x_chip_info *chip, u8 reg, u8 *data, int len)
-{
-	struct i2c_client *client = chip->client;
-	int ret;
-
-	ret = i2c_master_send(client, &reg, 1);
-	if (ret < 0) {
-		dev_err(&client->dev, "I2C write error\n");
-		return ret;
-	}
-
-	ret = i2c_master_recv(client, data, len);
-	if (ret < 0) {
-		dev_err(&client->dev, "I2C read error\n");
-		return ret;
-	}
-
-	return ret;
-}
-
-static int ad774x_i2c_write(struct ad774x_chip_info *chip, u8 reg, u8 data)
-{
-	struct i2c_client *client = chip->client;
-	int ret;
-
-	u8 tx[2] = {
-		reg,
-		data,
-	};
-
-	ret = i2c_master_send(client, tx, 2);
-	if (ret < 0)
-		dev_err(&client->dev, "I2C write error\n");
-
-	return ret;
-}
-
-/*
- * sysfs nodes
- */
-
-#define IIO_DEV_ATTR_AVAIL_CONVERSION_MODES(_show)				\
-	IIO_DEVICE_ATTR(available_conversion_modes, S_IRUGO, _show, NULL, 0)
-#define IIO_DEV_ATTR_CONVERSION_MODE(_mode, _show, _store)              \
-	IIO_DEVICE_ATTR(conversion_mode, _mode, _show, _store, 0)
-#define IIO_DEV_ATTR_CAP_SETUP(_mode, _show, _store)		\
-	IIO_DEVICE_ATTR(cap_setup, _mode, _show, _store, 0)
-#define IIO_DEV_ATTR_VT_SETUP(_mode, _show, _store)              \
-	IIO_DEVICE_ATTR(in0_setup, _mode, _show, _store, 0)
-#define IIO_DEV_ATTR_EXEC_SETUP(_mode, _show, _store)              \
-	IIO_DEVICE_ATTR(exec_setup, _mode, _show, _store, 0)
-#define IIO_DEV_ATTR_VOLT_GAIN(_mode, _show, _store)		\
-	IIO_DEVICE_ATTR(in0_gain, _mode, _show, _store, 0)
-#define IIO_DEV_ATTR_CAP_OFFS(_mode, _show, _store)		\
-	IIO_DEVICE_ATTR(cap_offs, _mode, _show, _store, 0)
-#define IIO_DEV_ATTR_CAP_GAIN(_mode, _show, _store)		\
-	IIO_DEVICE_ATTR(cap_gain, _mode, _show, _store, 0)
-#define IIO_DEV_ATTR_CAP_DATA(_show)		\
-	IIO_DEVICE_ATTR(cap0_raw, S_IRUGO, _show, NULL, 0)
-#define IIO_DEV_ATTR_VT_DATA(_show)		\
-	IIO_DEVICE_ATTR(in0_raw, S_IRUGO, _show, NULL, 0)
-
-static ssize_t ad774x_show_conversion_modes(struct device *dev,
-		struct device_attribute *attr,
-		char *buf)
-{
-	int i;
-	int len = 0;
-
-	for (i = 0; i < AD774X_MAX_CONV_MODE; i++)
-		len += sprintf(buf + len, "%s ", ad774x_conv_mode_table[i].name);
-
-	len += sprintf(buf + len, "\n");
-
-	return len;
-}
-
-static IIO_DEV_ATTR_AVAIL_CONVERSION_MODES(ad774x_show_conversion_modes);
-
-static ssize_t ad774x_show_conversion_mode(struct device *dev,
-		struct device_attribute *attr,
-		char *buf)
-{
-	struct iio_dev *dev_info = dev_get_drvdata(dev);
-	struct ad774x_chip_info *chip = iio_priv(dev_info);
-
-	return sprintf(buf, "%s\n", chip->conversion_mode);
-}
-
-static ssize_t ad774x_store_conversion_mode(struct device *dev,
-		struct device_attribute *attr,
-		const char *buf,
-		size_t len)
-{
-	struct iio_dev *dev_info = dev_get_drvdata(dev);
-	struct ad774x_chip_info *chip = iio_priv(dev_info);
-	u8 cfg;
-	int i;
-
-	ad774x_i2c_read(chip, AD774X_CFG, &cfg, 1);
-
-	for (i = 0; i < AD774X_MAX_CONV_MODE; i++) {
-		if (strncmp(buf, ad774x_conv_mode_table[i].name,
-				strlen(ad774x_conv_mode_table[i].name) - 1) == 0) {
-			chip->conversion_mode = ad774x_conv_mode_table[i].name;
-			cfg |= 0x18 | ad774x_conv_mode_table[i].reg_cfg;
-			ad774x_i2c_write(chip, AD774X_CFG, cfg);
-			return len;
-		}
-	}
-
-	dev_err(dev, "not supported conversion mode\n");
-
-	return -EINVAL;
-}
-
-static IIO_DEV_ATTR_CONVERSION_MODE(S_IRUGO | S_IWUSR,
-		ad774x_show_conversion_mode,
-		ad774x_store_conversion_mode);
-
-static ssize_t ad774x_show_dac_value(struct device *dev,
-		struct device_attribute *attr,
-		char *buf)
-{
-	struct iio_dev *dev_info = dev_get_drvdata(dev);
-	struct ad774x_chip_info *chip = iio_priv(dev_info);
-	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
-	u8 data;
-
-	ad774x_i2c_read(chip, this_attr->address, &data, 1);
-
-	return sprintf(buf, "%02x\n", data & 0x7F);
-}
-
-static ssize_t ad774x_store_dac_value(struct device *dev,
-		struct device_attribute *attr,
-		const char *buf,
-		size_t len)
-{
-	struct iio_dev *dev_info = dev_get_drvdata(dev);
-	struct ad774x_chip_info *chip = iio_priv(dev_info);
-	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
-	unsigned long data;
-	int ret;
-
-	ret = strict_strtoul(buf, 10, &data);
-
-	if (!ret) {
-		ad774x_i2c_write(chip, this_attr->address,
-			(data ? AD774X_CAPDAC_EN : 0) | (data & 0x7F));
-		return len;
-	}
-
-	return -EINVAL;
-}
-
-static IIO_DEVICE_ATTR(capdac0_raw, S_IRUGO | S_IWUSR,
-			ad774x_show_dac_value,
-			ad774x_store_dac_value,
-			AD774X_CAPDACA);
-
-static IIO_DEVICE_ATTR(capdac1_raw, S_IRUGO | S_IWUSR,
-			ad774x_show_dac_value,
-			ad774x_store_dac_value,
-			AD774X_CAPDACB);
-
-static ssize_t ad774x_show_cap_setup(struct device *dev,
-		struct device_attribute *attr,
-		char *buf)
-{
-	struct iio_dev *dev_info = dev_get_drvdata(dev);
-	struct ad774x_chip_info *chip = iio_priv(dev_info);
-
-	return sprintf(buf, "0x%02x\n", chip->cap_setup);
-}
-
-static ssize_t ad774x_store_cap_setup(struct device *dev,
-		struct device_attribute *attr,
-		const char *buf,
-		size_t len)
-{
-	struct iio_dev *dev_info = dev_get_drvdata(dev);
-	struct ad774x_chip_info *chip = iio_priv(dev_info);
-	unsigned long data;
-	int ret;
-
-	ret = strict_strtoul(buf, 10, &data);
-
-	if ((!ret) && (data < 0x100)) {
-		ad774x_i2c_write(chip, AD774X_CAP_SETUP, data);
-		chip->cap_setup = data;
-		return len;
-	}
-
-	return -EINVAL;
-}
-
-static IIO_DEV_ATTR_CAP_SETUP(S_IRUGO | S_IWUSR,
-		ad774x_show_cap_setup,
-		ad774x_store_cap_setup);
-
-static ssize_t ad774x_show_vt_setup(struct device *dev,
-		struct device_attribute *attr,
-		char *buf)
-{
-	struct iio_dev *dev_info = dev_get_drvdata(dev);
-	struct ad774x_chip_info *chip = iio_priv(dev_info);
-
-	return sprintf(buf, "0x%02x\n", chip->vt_setup);
-}
-
-static ssize_t ad774x_store_vt_setup(struct device *dev,
-		struct device_attribute *attr,
-		const char *buf,
-		size_t len)
-{
-	struct iio_dev *dev_info = dev_get_drvdata(dev);
-	struct ad774x_chip_info *chip = iio_priv(dev_info);
-	unsigned long data;
-	int ret;
-
-	ret = strict_strtoul(buf, 10, &data);
-
-	if ((!ret) && (data < 0x100)) {
-		ad774x_i2c_write(chip, AD774X_VT_SETUP, data);
-		chip->vt_setup = data;
-		return len;
-	}
-
-	return -EINVAL;
-}
-
-static IIO_DEV_ATTR_VT_SETUP(S_IRUGO | S_IWUSR,
-		ad774x_show_vt_setup,
-		ad774x_store_vt_setup);
-
-static ssize_t ad774x_show_exec_setup(struct device *dev,
-		struct device_attribute *attr,
-		char *buf)
-{
-	struct iio_dev *dev_info = dev_get_drvdata(dev);
-	struct ad774x_chip_info *chip = iio_priv(dev_info);
-
-	return sprintf(buf, "0x%02x\n", chip->exec_setup);
-}
-
-static ssize_t ad774x_store_exec_setup(struct device *dev,
-		struct device_attribute *attr,
-		const char *buf,
-		size_t len)
-{
-	struct iio_dev *dev_info = dev_get_drvdata(dev);
-	struct ad774x_chip_info *chip = iio_priv(dev_info);
-	unsigned long data;
-	int ret;
-
-	ret = strict_strtoul(buf, 10, &data);
-
-	if ((!ret) && (data < 0x100)) {
-		ad774x_i2c_write(chip, AD774X_EXEC_SETUP, data);
-		chip->exec_setup = data;
-		return len;
-	}
-
-	return -EINVAL;
-}
-
-static IIO_DEV_ATTR_EXEC_SETUP(S_IRUGO | S_IWUSR,
-		ad774x_show_exec_setup,
-		ad774x_store_exec_setup);
-
-static ssize_t ad774x_show_volt_gain(struct device *dev,
-		struct device_attribute *attr,
-		char *buf)
-{
-	struct iio_dev *dev_info = dev_get_drvdata(dev);
-	struct ad774x_chip_info *chip = iio_priv(dev_info);
-
-	return sprintf(buf, "%d\n", chip->volt_gain);
-}
-
-static ssize_t ad774x_store_volt_gain(struct device *dev,
-		struct device_attribute *attr,
-		const char *buf,
-		size_t len)
-{
-	struct iio_dev *dev_info = dev_get_drvdata(dev);
-	struct ad774x_chip_info *chip = iio_priv(dev_info);
-	unsigned long data;
-	int ret;
-
-	ret = strict_strtoul(buf, 10, &data);
-
-	if ((!ret) && (data < 0x10000)) {
-		ad774x_i2c_write(chip, AD774X_VOLT_GAINH, data >> 8);
-		ad774x_i2c_write(chip, AD774X_VOLT_GAINL, data);
-		chip->volt_gain = data;
-		return len;
-	}
-
-	return -EINVAL;
-}
-
-static IIO_DEV_ATTR_VOLT_GAIN(S_IRUGO | S_IWUSR,
-		ad774x_show_volt_gain,
-		ad774x_store_volt_gain);
-
-static ssize_t ad774x_show_cap_data(struct device *dev,
-		struct device_attribute *attr,
-		char *buf)
-{
-	struct iio_dev *dev_info = dev_get_drvdata(dev);
-	struct ad774x_chip_info *chip = iio_priv(dev_info);
-	unsigned long data;
-	char tmp[3];
-
-	ad774x_i2c_read(chip, AD774X_CAP_DATA_HIGH, tmp, 3);
-	data = ((int)tmp[0] << 16) | ((int)tmp[1] << 8) | (int)tmp[2];
-
-	return sprintf(buf, "%ld\n", data);
-}
-
-static IIO_DEV_ATTR_CAP_DATA(ad774x_show_cap_data);
-
-static ssize_t ad774x_show_vt_data(struct device *dev,
-		struct device_attribute *attr,
-		char *buf)
-{
-	struct iio_dev *dev_info = dev_get_drvdata(dev);
-	struct ad774x_chip_info *chip = iio_priv(dev_info);
-	unsigned long data;
-	char tmp[3];
-
-	ad774x_i2c_read(chip, AD774X_VT_DATA_HIGH, tmp, 3);
-	data = ((int)tmp[0] << 16) | ((int)tmp[1] << 8) | (int)tmp[2];
-
-	return sprintf(buf, "%ld\n", data);
-}
-
-static IIO_DEV_ATTR_VT_DATA(ad774x_show_vt_data);
-
-static ssize_t ad774x_show_cap_offs(struct device *dev,
-		struct device_attribute *attr,
-		char *buf)
-{
-	struct iio_dev *dev_info = dev_get_drvdata(dev);
-	struct ad774x_chip_info *chip = iio_priv(dev_info);
-
-	return sprintf(buf, "%d\n", chip->cap_offs);
-}
-
-static ssize_t ad774x_store_cap_offs(struct device *dev,
-		struct device_attribute *attr,
-		const char *buf,
-		size_t len)
-{
-	struct iio_dev *dev_info = dev_get_drvdata(dev);
-	struct ad774x_chip_info *chip = iio_priv(dev_info);
-	unsigned long data;
-	int ret;
-
-	ret = strict_strtoul(buf, 10, &data);
-
-	if ((!ret) && (data < 0x10000)) {
-		ad774x_i2c_write(chip, AD774X_CAP_OFFH, data >> 8);
-		ad774x_i2c_write(chip, AD774X_CAP_OFFL, data);
-		chip->cap_offs = data;
-		return len;
-	}
-
-	return -EINVAL;
-}
-
-static IIO_DEV_ATTR_CAP_OFFS(S_IRUGO | S_IWUSR,
-		ad774x_show_cap_offs,
-		ad774x_store_cap_offs);
-
-static ssize_t ad774x_show_cap_gain(struct device *dev,
-		struct device_attribute *attr,
-		char *buf)
-{
-	struct iio_dev *dev_info = dev_get_drvdata(dev);
-	struct ad774x_chip_info *chip = iio_priv(dev_info);
-
-	return sprintf(buf, "%d\n", chip->cap_gain);
-}
-
-static ssize_t ad774x_store_cap_gain(struct device *dev,
-		struct device_attribute *attr,
-		const char *buf,
-		size_t len)
-{
-	struct iio_dev *dev_info = dev_get_drvdata(dev);
-	struct ad774x_chip_info *chip = iio_priv(dev_info);
-	unsigned long data;
-	int ret;
-
-	ret = strict_strtoul(buf, 10, &data);
-
-	if ((!ret) && (data < 0x10000)) {
-		ad774x_i2c_write(chip, AD774X_CAP_GAINH, data >> 8);
-		ad774x_i2c_write(chip, AD774X_CAP_GAINL, data);
-		chip->cap_gain = data;
-		return len;
-	}
-
-	return -EINVAL;
-}
-
-static IIO_DEV_ATTR_CAP_GAIN(S_IRUGO | S_IWUSR,
-		ad774x_show_cap_gain,
-		ad774x_store_cap_gain);
-
-static struct attribute *ad774x_attributes[] = {
-	&iio_dev_attr_available_conversion_modes.dev_attr.attr,
-	&iio_dev_attr_conversion_mode.dev_attr.attr,
-	&iio_dev_attr_cap_setup.dev_attr.attr,
-	&iio_dev_attr_in0_setup.dev_attr.attr,
-	&iio_dev_attr_exec_setup.dev_attr.attr,
-	&iio_dev_attr_cap_offs.dev_attr.attr,
-	&iio_dev_attr_cap_gain.dev_attr.attr,
-	&iio_dev_attr_in0_gain.dev_attr.attr,
-	&iio_dev_attr_in0_raw.dev_attr.attr,
-	&iio_dev_attr_cap0_raw.dev_attr.attr,
-	&iio_dev_attr_capdac0_raw.dev_attr.attr,
-	&iio_dev_attr_capdac1_raw.dev_attr.attr,
-	NULL,
-};
-
-static const struct attribute_group ad774x_attribute_group = {
-	.attrs = ad774x_attributes,
-};
-
-/*
- * data ready events
- */
-
-#define IIO_EVENT_CODE_CAP_RDY     0
-#define IIO_EVENT_CODE_VT_RDY      1
-
-#define IIO_EVENT_ATTR_CAP_RDY_SH(_evlist, _show, _store, _mask)	\
-	IIO_EVENT_ATTR_SH(cap_rdy, _evlist, _show, _store, _mask)
-
-#define IIO_EVENT_ATTR_VT_RDY_SH(_evlist, _show, _store, _mask)	\
-	IIO_EVENT_ATTR_SH(vt_rdy, _evlist, _show, _store, _mask)
-
-static irqreturn_t ad774x_event_handler(int irq, void *private)
-{
-	struct iio_dev *indio_dev = private;
-	struct ad774x_chip_info *chip = iio_priv(indio_dev);
-	u8 int_status;
-
-	ad774x_i2c_read(chip, AD774X_STATUS, &int_status, 1);
-
-	if (int_status & AD774X_STATUS_RDYCAP)
-		iio_push_event(indio_dev,
-			       IIO_EVENT_CODE_CAP_RDY,
-			       iio_get_time_ns());
-
-	if (int_status & AD774X_STATUS_RDYVT)
-		iio_push_event(indio_dev,
-			       IIO_EVENT_CODE_VT_RDY,
-			       iio_get_time_ns());
-
-	return IRQ_HANDLED;
-}
-
-static IIO_CONST_ATTR(cap_rdy_en, "1");
-static IIO_CONST_ATTR(vt_rdy_en, "1");
-
-static struct attribute *ad774x_event_attributes[] = {
-	&iio_const_attr_cap_rdy_en.dev_attr.attr,
-	&iio_const_attr_vt_rdy_en.dev_attr.attr,
-	NULL,
-};
-
-static struct attribute_group ad774x_event_attribute_group = {
-	.attrs = ad774x_event_attributes,
-	.name = "events",
-};
-
-static const struct iio_info ad774x_info = {
-	.attrs = &ad774x_event_attribute_group,
-	.event_attrs = &ad774x_event_attribute_group,
-	.driver_module = THIS_MODULE,
-};
-/*
- * device probe and remove
- */
-
-static int __devinit ad774x_probe(struct i2c_client *client,
-		const struct i2c_device_id *id)
-{
-	int ret;
-	struct ad774x_chip_info *chip;
-	struct iio_dev *indio_dev;
-
-	indio_dev = iio_allocate_device(sizeof(*chip));
-	if (indio_dev == NULL) {
-		ret = -ENOMEM;
-		goto error_ret;
-	}
-	chip = iio_priv(indio_dev);
-	/* this is only used for device removal purposes */
-	i2c_set_clientdata(client, indio_dev);
-
-	chip->client = client;
-
-	/* Establish that the iio_dev is a child of the i2c device */
-	indio_dev->name = id->name;
-	indio_dev->dev.parent = &client->dev;
-	indio_dev->info = &ad774x_info;
-	indio_dev->modes = INDIO_DIRECT_MODE;
-
-	if (client->irq) {
-		ret = request_threaded_irq(client->irq,
-					   NULL,
-					   &ad774x_event_handler,
-					   IRQF_TRIGGER_FALLING,
-					   "ad774x",
-					   indio_dev);
-		if (ret)
-			goto error_free_dev;
-	}
-
-	ret = iio_device_register(indio_dev);
-	if (ret)
-		goto error_free_irq;
-
-	dev_err(&client->dev, "%s capacitive sensor registered, irq: %d\n", id->name, client->irq);
-
-	return 0;
-
-error_free_irq:
-	free_irq(client->irq, indio_dev);
-error_free_dev:
-	iio_free_device(indio_dev);
-error_ret:
-	return ret;
-}
-
-static int __devexit ad774x_remove(struct i2c_client *client)
-{
-	struct iio_dev *indio_dev = i2c_get_clientdata(client);
-
-	if (client->irq)
-		free_irq(client->irq, indio_dev);
-	iio_device_unregister(indio_dev);
-
-	return 0;
-}
-
-static const struct i2c_device_id ad774x_id[] = {
-	{ "ad7745", 0 },
-	{ "ad7746", 0 },
-	{ "ad7747", 0 },
-	{}
-};
-
-MODULE_DEVICE_TABLE(i2c, ad774x_id);
-
-static struct i2c_driver ad774x_driver = {
-	.driver = {
-		.name = "ad774x",
-	},
-	.probe = ad774x_probe,
-	.remove = __devexit_p(ad774x_remove),
-	.id_table = ad774x_id,
-};
-
-static __init int ad774x_init(void)
-{
-	return i2c_add_driver(&ad774x_driver);
-}
-
-static __exit void ad774x_exit(void)
-{
-	i2c_del_driver(&ad774x_driver);
-}
-
-MODULE_AUTHOR("Barry Song <21cnbao@gmail.com>");
-MODULE_DESCRIPTION("Analog Devices ad7745/6/7 capacitive sensor driver");
-MODULE_LICENSE("GPL v2");
-
-module_init(ad774x_init);
-module_exit(ad774x_exit);
diff --git a/drivers/staging/iio/adc/ad7746.c b/drivers/staging/iio/adc/ad7746.c
new file mode 100644
index 0000000..a6003a0
--- /dev/null
+++ b/drivers/staging/iio/adc/ad7746.c
@@ -0,0 +1,801 @@
+/*
+ * AD7746 capacitive sensor driver supporting AD7745, AD7746 and AD7747
+ *
+ * Copyright 2011 Analog Devices Inc.
+ *
+ * Licensed under the GPL-2.
+ */
+
+#include <linux/interrupt.h>
+#include <linux/device.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/sysfs.h>
+#include <linux/i2c.h>
+#include <linux/delay.h>
+
+#include "../iio.h"
+#include "../sysfs.h"
+
+#include "ad7746.h"
+
+/*
+ * AD7746 Register Definition
+ */
+
+#define AD7746_REG_STATUS		0
+#define AD7746_REG_CAP_DATA_HIGH	1
+#define AD7746_REG_CAP_DATA_MID		2
+#define AD7746_REG_CAP_DATA_LOW		3
+#define AD7746_REG_VT_DATA_HIGH		4
+#define AD7746_REG_VT_DATA_MID		5
+#define AD7746_REG_VT_DATA_LOW		6
+#define AD7746_REG_CAP_SETUP		7
+#define AD7746_REG_VT_SETUP		8
+#define AD7746_REG_EXC_SETUP		9
+#define AD7746_REG_CFG			10
+#define AD7746_REG_CAPDACA		11
+#define AD7746_REG_CAPDACB		12
+#define AD7746_REG_CAP_OFFH		13
+#define AD7746_REG_CAP_OFFL		14
+#define AD7746_REG_CAP_GAINH		15
+#define AD7746_REG_CAP_GAINL		16
+#define AD7746_REG_VOLT_GAINH		17
+#define AD7746_REG_VOLT_GAINL		18
+
+/* Status Register Bit Designations (AD7746_REG_STATUS) */
+#define AD7746_STATUS_EXCERR		(1 << 3)
+#define AD7746_STATUS_RDY		(1 << 2)
+#define AD7746_STATUS_RDYVT		(1 << 1)
+#define AD7746_STATUS_RDYCAP		(1 << 0)
+
+/* Capacitive Channel Setup Register Bit Designations (AD7746_REG_CAP_SETUP) */
+#define AD7746_CAPSETUP_CAPEN		(1 << 7)
+#define AD7746_CAPSETUP_CIN2		(1 << 6) /* AD7746 only */
+#define AD7746_CAPSETUP_CAPDIFF		(1 << 5)
+#define AD7746_CAPSETUP_CACHOP		(1 << 0)
+
+/* Voltage/Temperature Setup Register Bit Designations (AD7746_REG_VT_SETUP) */
+#define AD7746_VTSETUP_VTEN		(1 << 7)
+#define AD7746_VTSETUP_VTMD_INT_TEMP	(0 << 5)
+#define AD7746_VTSETUP_VTMD_EXT_TEMP	(1 << 5)
+#define AD7746_VTSETUP_VTMD_VDD_MON	(2 << 5)
+#define AD7746_VTSETUP_VTMD_EXT_VIN	(3 << 5)
+#define AD7746_VTSETUP_EXTREF		(1 << 4)
+#define AD7746_VTSETUP_VTSHORT		(1 << 1)
+#define AD7746_VTSETUP_VTCHOP		(1 << 0)
+
+/* Excitation Setup Register Bit Designations (AD7746_REG_EXC_SETUP) */
+#define AD7746_EXCSETUP_CLKCTRL		(1 << 7)
+#define AD7746_EXCSETUP_EXCON		(1 << 6)
+#define AD7746_EXCSETUP_EXCB		(1 << 5)
+#define AD7746_EXCSETUP_NEXCB		(1 << 4)
+#define AD7746_EXCSETUP_EXCA		(1 << 3)
+#define AD7746_EXCSETUP_NEXCA		(1 << 2)
+#define AD7746_EXCSETUP_EXCLVL(x)	(((x) & 0x3) << 0)
+
+/* Config Register Bit Designations (AD7746_REG_CFG) */
+#define AD7746_CONF_VTFS(x)		((x) << 6)
+#define AD7746_CONF_CAPFS(x)		((x) << 3)
+#define AD7746_CONF_MODE_IDLE		(0 << 0)
+#define AD7746_CONF_MODE_CONT_CONV	(1 << 0)
+#define AD7746_CONF_MODE_SINGLE_CONV	(2 << 0)
+#define AD7746_CONF_MODE_PWRDN		(3 << 0)
+#define AD7746_CONF_MODE_OFFS_CAL	(5 << 0)
+#define AD7746_CONF_MODE_GAIN_CAL	(6 << 0)
+
+/* CAPDAC Register Bit Designations (AD7746_REG_CAPDACx) */
+#define AD7746_CAPDAC_DACEN		(1 << 7)
+#define AD7746_CAPDAC_DACP(x)		((x) & 0x7F)
+
+/*
+ * struct ad7746_chip_info - chip specifc information
+ */
+
+struct ad7746_chip_info {
+	struct i2c_client *client;
+	/*
+	 * Capacitive channel digital filter setup;
+	 * conversion time/update rate setup per channel
+	 */
+	u8	config;
+	u8	cap_setup;
+	u8	vt_setup;
+	u8	capdac[2][2];
+	s8	capdac_set;
+};
+
+enum ad7746_chan {
+	VIN,
+	VIN_VDD,
+	TEMP_INT,
+	TEMP_EXT,
+	CIN1,
+	CIN1_DIFF,
+	CIN2,
+	CIN2_DIFF,
+};
+
+static const struct iio_chan_spec ad7746_channels[] = {
+	[VIN] = {
+		.type = IIO_VOLTAGE,
+		.indexed = 1,
+		.channel = 0,
+		.info_mask = (1 << IIO_CHAN_INFO_SCALE_SHARED) |
+		(1 << IIO_CHAN_INFO_SCALE_SEPARATE),
+		.address = AD7746_REG_VT_DATA_HIGH << 8 |
+			AD7746_VTSETUP_VTMD_EXT_VIN,
+	},
+	[VIN_VDD] = {
+		.type = IIO_VOLTAGE,
+		.indexed = 1,
+		.channel = 1,
+		.extend_name = "supply",
+		.info_mask = (1 << IIO_CHAN_INFO_SCALE_SHARED),
+		.address = AD7746_REG_VT_DATA_HIGH << 8 |
+			AD7746_VTSETUP_VTMD_VDD_MON,
+	},
+	[TEMP_INT] = {
+		.type = IIO_TEMP,
+		.indexed = 1,
+		.channel = 0,
+		.processed_val = IIO_PROCESSED,
+		.address = AD7746_REG_VT_DATA_HIGH << 8 |
+			AD7746_VTSETUP_VTMD_INT_TEMP,
+	},
+	[TEMP_EXT] = {
+		.type = IIO_TEMP,
+		.indexed = 1,
+		.channel = 1,
+		.processed_val = IIO_PROCESSED,
+		.address = AD7746_REG_VT_DATA_HIGH << 8 |
+			AD7746_VTSETUP_VTMD_EXT_TEMP,
+	},
+	[CIN1] = {
+		.type = IIO_CAPACITANCE,
+		.indexed = 1,
+		.channel = 0,
+		.info_mask = (1 << IIO_CHAN_INFO_CALIBSCALE_SEPARATE) |
+		(1 << IIO_CHAN_INFO_CALIBBIAS_SHARED) |
+		(1 << IIO_CHAN_INFO_OFFSET_SEPARATE) |
+		(1 << IIO_CHAN_INFO_SCALE_SHARED),
+		.address = AD7746_REG_CAP_DATA_HIGH << 8,
+	},
+	[CIN1_DIFF] = {
+		.type = IIO_CAPACITANCE,
+		.differential = 1,
+		.indexed = 1,
+		.channel = 0,
+		.channel2 = 2,
+		.info_mask = (1 << IIO_CHAN_INFO_CALIBSCALE_SEPARATE) |
+		(1 << IIO_CHAN_INFO_CALIBBIAS_SHARED) |
+		(1 << IIO_CHAN_INFO_OFFSET_SEPARATE) |
+		(1 << IIO_CHAN_INFO_SCALE_SHARED),
+		.address = AD7746_REG_CAP_DATA_HIGH << 8 |
+			AD7746_CAPSETUP_CAPDIFF
+	},
+	[CIN2] = {
+		.type = IIO_CAPACITANCE,
+		.indexed = 1,
+		.channel = 1,
+		.info_mask = (1 << IIO_CHAN_INFO_CALIBSCALE_SEPARATE) |
+		(1 << IIO_CHAN_INFO_CALIBBIAS_SHARED) |
+		(1 << IIO_CHAN_INFO_OFFSET_SEPARATE) |
+		(1 << IIO_CHAN_INFO_SCALE_SHARED),
+		.address = AD7746_REG_CAP_DATA_HIGH << 8 |
+			AD7746_CAPSETUP_CIN2,
+	},
+	[CIN2_DIFF] = {
+		.type = IIO_CAPACITANCE,
+		.differential = 1,
+		.indexed = 1,
+		.channel = 1,
+		.channel2 = 3,
+		.info_mask = (1 << IIO_CHAN_INFO_CALIBSCALE_SEPARATE) |
+		(1 << IIO_CHAN_INFO_CALIBBIAS_SHARED) |
+		(1 << IIO_CHAN_INFO_OFFSET_SEPARATE) |
+		(1 << IIO_CHAN_INFO_SCALE_SHARED),
+		.address = AD7746_REG_CAP_DATA_HIGH << 8 |
+			AD7746_CAPSETUP_CAPDIFF | AD7746_CAPSETUP_CIN2,
+	}
+};
+
+/* Values are Update Rate (Hz), Conversion Time (ms) + 1*/
+static const unsigned char ad7746_vt_filter_rate_table[][2] = {
+	{50, 20 + 1}, {31, 32 + 1}, {16, 62 + 1}, {8, 122 + 1},
+};
+
+static const unsigned char ad7746_cap_filter_rate_table[][2] = {
+	{91, 11 + 1}, {84, 12 + 1}, {50, 20 + 1}, {26, 38 + 1},
+	{16, 62 + 1}, {13, 77 + 1}, {11, 92 + 1}, {9, 110 + 1},
+};
+
+static int ad7746_select_channel(struct iio_dev *indio_dev,
+			    struct iio_chan_spec const *chan)
+{
+	struct ad7746_chip_info *chip = iio_priv(indio_dev);
+	int ret, delay;
+	u8 vt_setup, cap_setup;
+
+	switch (chan->type) {
+	case IIO_CAPACITANCE:
+		cap_setup = (chan->address & 0xFF) | AD7746_CAPSETUP_CAPEN;
+		vt_setup = chip->vt_setup & ~AD7746_VTSETUP_VTEN;
+		delay = ad7746_cap_filter_rate_table[(chip->config >> 3) &
+			0x7][1];
+
+		if (chip->capdac_set != chan->channel) {
+			ret = i2c_smbus_write_byte_data(chip->client,
+				AD7746_REG_CAPDACA,
+				chip->capdac[chan->channel][0]);
+			if (ret < 0)
+				return ret;
+			ret = i2c_smbus_write_byte_data(chip->client,
+				AD7746_REG_CAPDACB,
+				chip->capdac[chan->channel][1]);
+			if (ret < 0)
+				return ret;
+
+			chip->capdac_set = chan->channel;
+		}
+		break;
+	case IIO_VOLTAGE:
+	case IIO_TEMP:
+		vt_setup = (chan->address & 0xFF) | AD7746_VTSETUP_VTEN;
+		cap_setup = chip->cap_setup & ~AD7746_CAPSETUP_CAPEN;
+		delay = ad7746_cap_filter_rate_table[(chip->config >> 6) &
+			0x3][1];
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	if (chip->cap_setup != cap_setup) {
+		ret = i2c_smbus_write_byte_data(chip->client,
+						AD7746_REG_CAP_SETUP,
+						cap_setup);
+		if (ret < 0)
+			return ret;
+
+		chip->cap_setup = cap_setup;
+	}
+
+	if (chip->vt_setup != vt_setup) {
+		ret = i2c_smbus_write_byte_data(chip->client,
+						AD7746_REG_VT_SETUP,
+						vt_setup);
+		if (ret < 0)
+			return ret;
+
+		chip->vt_setup = vt_setup;
+	}
+
+	return delay;
+}
+
+static inline ssize_t ad7746_start_calib(struct device *dev,
+					 struct device_attribute *attr,
+					 const char *buf,
+					 size_t len,
+					 u8 regval)
+{
+	struct iio_dev *indio_dev = dev_get_drvdata(dev);
+	struct ad7746_chip_info *chip = iio_priv(indio_dev);
+	bool doit;
+	int ret, timeout = 10;
+
+	ret = strtobool(buf, &doit);
+	if (ret < 0)
+		return ret;
+
+	if (!doit)
+		return 0;
+
+	mutex_lock(&indio_dev->mlock);
+	regval |= chip->config;
+	ret = i2c_smbus_write_byte_data(chip->client, AD7746_REG_CFG, regval);
+	if (ret < 0) {
+		mutex_unlock(&indio_dev->mlock);
+		return ret;
+	}
+
+	do {
+		msleep(20);
+		ret = i2c_smbus_read_byte_data(chip->client, AD7746_REG_CFG);
+		if (ret < 0) {
+			mutex_unlock(&indio_dev->mlock);
+			return ret;
+		}
+	} while ((ret == regval) && timeout--);
+
+	mutex_unlock(&indio_dev->mlock);
+	return len;
+}
+static ssize_t ad7746_start_offset_calib(struct device *dev,
+					 struct device_attribute *attr,
+					 const char *buf,
+					 size_t len)
+{
+	struct iio_dev *indio_dev = dev_get_drvdata(dev);
+	int ret = ad7746_select_channel(indio_dev,
+			      &ad7746_channels[to_iio_dev_attr(attr)->address]);
+	if (ret < 0)
+		return ret;
+
+	return ad7746_start_calib(dev, attr, buf, len,
+				  AD7746_CONF_MODE_OFFS_CAL);
+}
+static ssize_t ad7746_start_gain_calib(struct device *dev,
+				       struct device_attribute *attr,
+				       const char *buf,
+				       size_t len)
+{
+	struct iio_dev *indio_dev = dev_get_drvdata(dev);
+	int ret = ad7746_select_channel(indio_dev,
+			      &ad7746_channels[to_iio_dev_attr(attr)->address]);
+	if (ret < 0)
+		return ret;
+
+	return ad7746_start_calib(dev, attr, buf, len,
+				  AD7746_CONF_MODE_GAIN_CAL);
+}
+
+static IIO_DEVICE_ATTR(in_capacitance0_calibbias_calibration,
+		       S_IWUSR, NULL, ad7746_start_offset_calib, CIN1);
+static IIO_DEVICE_ATTR(in_capacitance1_calibbias_calibration,
+		       S_IWUSR, NULL, ad7746_start_offset_calib, CIN2);
+static IIO_DEVICE_ATTR(in_capacitance0_calibscale_calibration,
+		       S_IWUSR, NULL, ad7746_start_gain_calib, CIN1);
+static IIO_DEVICE_ATTR(in_capacitance1_calibscale_calibration,
+		       S_IWUSR, NULL, ad7746_start_gain_calib, CIN2);
+static IIO_DEVICE_ATTR(in_voltage0_calibscale_calibration,
+		       S_IWUSR, NULL, ad7746_start_gain_calib, VIN);
+
+static ssize_t ad7746_show_cap_filter_rate_setup(struct device *dev,
+		struct device_attribute *attr,
+		char *buf)
+{
+	struct iio_dev *indio_dev = dev_get_drvdata(dev);
+	struct ad7746_chip_info *chip = iio_priv(indio_dev);
+
+	return sprintf(buf, "%d\n", ad7746_cap_filter_rate_table[
+			(chip->config >> 3) & 0x7][0]);
+}
+
+static ssize_t ad7746_store_cap_filter_rate_setup(struct device *dev,
+		struct device_attribute *attr,
+		const char *buf,
+		size_t len)
+{
+	struct iio_dev *indio_dev = dev_get_drvdata(dev);
+	struct ad7746_chip_info *chip = iio_priv(indio_dev);
+	u8 data;
+	int ret, i;
+
+	ret = kstrtou8(buf, 10, &data);
+	if (ret < 0)
+		return ret;
+
+	for (i = 0; i < ARRAY_SIZE(ad7746_cap_filter_rate_table); i++)
+		if (data >= ad7746_cap_filter_rate_table[i][0])
+			break;
+
+	if (i >= ARRAY_SIZE(ad7746_cap_filter_rate_table))
+		i = ARRAY_SIZE(ad7746_cap_filter_rate_table) - 1;
+
+	mutex_lock(&indio_dev->mlock);
+	chip->config &= ~AD7746_CONF_CAPFS(0x7);
+	chip->config |= AD7746_CONF_CAPFS(i);
+	mutex_unlock(&indio_dev->mlock);
+
+	return len;
+}
+
+static ssize_t ad7746_show_vt_filter_rate_setup(struct device *dev,
+		struct device_attribute *attr,
+		char *buf)
+{
+	struct iio_dev *indio_dev = dev_get_drvdata(dev);
+	struct ad7746_chip_info *chip = iio_priv(indio_dev);
+
+	return sprintf(buf, "%d\n", ad7746_vt_filter_rate_table[
+			(chip->config >> 6) & 0x3][0]);
+}
+
+static ssize_t ad7746_store_vt_filter_rate_setup(struct device *dev,
+		struct device_attribute *attr,
+		const char *buf,
+		size_t len)
+{
+	struct iio_dev *indio_dev = dev_get_drvdata(dev);
+	struct ad7746_chip_info *chip = iio_priv(indio_dev);
+	u8 data;
+	int ret, i;
+
+	ret = kstrtou8(buf, 10, &data);
+	if (ret < 0)
+		return ret;
+
+	for (i = 0; i < ARRAY_SIZE(ad7746_vt_filter_rate_table); i++)
+		if (data >= ad7746_vt_filter_rate_table[i][0])
+			break;
+
+	if (i >= ARRAY_SIZE(ad7746_vt_filter_rate_table))
+		i = ARRAY_SIZE(ad7746_vt_filter_rate_table) - 1;
+
+	mutex_lock(&indio_dev->mlock);
+	chip->config &= ~AD7746_CONF_VTFS(0x3);
+	chip->config |= AD7746_CONF_VTFS(i);
+	mutex_unlock(&indio_dev->mlock);
+
+	return len;
+}
+
+static IIO_DEVICE_ATTR(in_capacitance_sampling_frequency,
+		       S_IRUGO | S_IWUSR, ad7746_show_cap_filter_rate_setup,
+			ad7746_store_cap_filter_rate_setup, 0);
+
+static IIO_DEVICE_ATTR(in_voltage_sampling_frequency,
+		       S_IRUGO | S_IWUSR, ad7746_show_vt_filter_rate_setup,
+		       ad7746_store_vt_filter_rate_setup, 0);
+
+static IIO_CONST_ATTR(in_voltage_sampling_frequency_available, "50 31 16 8");
+static IIO_CONST_ATTR(in_capacitance_sampling_frequency_available,
+		       "91 84 50 26 16 13 11 9");
+
+static struct attribute *ad7746_attributes[] = {
+	&iio_dev_attr_in_capacitance_sampling_frequency.dev_attr.attr,
+	&iio_dev_attr_in_voltage_sampling_frequency.dev_attr.attr,
+	&iio_dev_attr_in_capacitance0_calibbias_calibration.dev_attr.attr,
+	&iio_dev_attr_in_capacitance0_calibscale_calibration.dev_attr.attr,
+	&iio_dev_attr_in_capacitance1_calibscale_calibration.dev_attr.attr,
+	&iio_dev_attr_in_capacitance1_calibbias_calibration.dev_attr.attr,
+	&iio_dev_attr_in_voltage0_calibscale_calibration.dev_attr.attr,
+	&iio_const_attr_in_voltage_sampling_frequency_available.dev_attr.attr,
+	&iio_const_attr_in_capacitance_sampling_frequency_available.
+	dev_attr.attr,
+	NULL,
+};
+
+static const struct attribute_group ad7746_attribute_group = {
+	.attrs = ad7746_attributes,
+};
+
+static int ad7746_write_raw(struct iio_dev *indio_dev,
+			    struct iio_chan_spec const *chan,
+			    int val,
+			    int val2,
+			    long mask)
+{
+	struct ad7746_chip_info *chip = iio_priv(indio_dev);
+	int ret, reg;
+
+	mutex_lock(&indio_dev->mlock);
+
+	switch (mask) {
+	case (1 << IIO_CHAN_INFO_CALIBSCALE_SEPARATE):
+		if (val != 1) {
+			ret = -EINVAL;
+			goto out;
+		}
+
+		val = (val2 * 1024) / 15625;
+
+		switch (chan->type) {
+		case IIO_CAPACITANCE:
+			reg = AD7746_REG_CAP_GAINH;
+			break;
+		case IIO_VOLTAGE:
+			reg = AD7746_REG_VOLT_GAINH;
+			break;
+		default:
+			ret = -EINVAL;
+			goto out;
+		}
+
+		ret = i2c_smbus_write_word_data(chip->client, reg, swab16(val));
+		if (ret < 0)
+			goto out;
+
+		ret = 0;
+		break;
+	case (1 << IIO_CHAN_INFO_CALIBBIAS_SHARED):
+		if ((val < 0) | (val > 0xFFFF)) {
+			ret = -EINVAL;
+			goto out;
+		}
+		ret = i2c_smbus_write_word_data(chip->client,
+				AD7746_REG_CAP_OFFH, swab16(val));
+		if (ret < 0)
+			goto out;
+
+		ret = 0;
+		break;
+	case (1 << IIO_CHAN_INFO_OFFSET_SEPARATE):
+		if ((val < 0) | (val > 44040192)) { /* 21pF */
+			ret = -EINVAL;
+			goto out;
+		}
+
+		/* CAPDAC Scale = 21pF_typ / 127
+		 * CIN Scale = 8pF / 2^24
+		 * Offset Scale = CAPDAC Scale / CIN Scale = 346773
+		 * */
+
+		val /= 346773;
+
+		chip->capdac[chan->channel][chan->differential] = (val > 0 ?
+			AD7746_CAPDAC_DACP(val) | AD7746_CAPDAC_DACEN : 0);
+
+		ret = i2c_smbus_write_byte_data(chip->client,
+			AD7746_REG_CAPDACA,
+			chip->capdac[chan->channel][0]);
+		if (ret < 0)
+			goto out;
+		ret = i2c_smbus_write_byte_data(chip->client,
+			AD7746_REG_CAPDACB,
+			chip->capdac[chan->channel][1]);
+		if (ret < 0)
+			goto out;
+
+		chip->capdac_set = chan->channel;
+
+		ret = 0;
+		break;
+	default:
+		ret = -EINVAL;
+	}
+
+out:
+	mutex_unlock(&indio_dev->mlock);
+	return ret;
+}
+static int ad7746_read_raw(struct iio_dev *indio_dev,
+			   struct iio_chan_spec const *chan,
+			   int *val, int *val2,
+			   long mask)
+{
+	struct ad7746_chip_info *chip = iio_priv(indio_dev);
+	int ret, delay;
+	u8 regval, reg;
+
+	union {
+		u32 d32;
+		u8 d8[4];
+	} data;
+
+	mutex_lock(&indio_dev->mlock);
+
+	switch (mask) {
+	case 0:
+		ret = ad7746_select_channel(indio_dev, chan);
+		if (ret < 0)
+			goto out;
+		delay = ret;
+
+		regval = chip->config | AD7746_CONF_MODE_SINGLE_CONV;
+		ret = i2c_smbus_write_byte_data(chip->client, AD7746_REG_CFG,
+				regval);
+		if (ret < 0)
+			goto out;
+
+		msleep(delay);
+		/* Now read the actual register */
+
+		ret = i2c_smbus_read_i2c_block_data(chip->client,
+			chan->address >> 8, 3, &data.d8[1]);
+
+		if (ret < 0)
+			goto out;
+
+		*val = (be32_to_cpu(data.d32) & 0xFFFFFF) - 0x800000;
+
+		switch (chan->type) {
+		case IIO_TEMP:
+		/* temperature in milli degrees Celsius
+		 * T = ((*val / 2048) - 4096) * 1000
+		 */
+			*val = (*val * 125) / 256;
+			break;
+		case IIO_VOLTAGE:
+			if (chan->channel == 1) /* supply_raw*/
+				*val = *val * 6;
+				break;
+		default:
+			break;
+		}
+
+		ret = IIO_VAL_INT;
+		break;
+	case (1 << IIO_CHAN_INFO_CALIBSCALE_SEPARATE):
+		switch (chan->type) {
+		case IIO_CAPACITANCE:
+			reg = AD7746_REG_CAP_GAINH;
+			break;
+		case IIO_VOLTAGE:
+			reg = AD7746_REG_VOLT_GAINH;
+			break;
+		default:
+			ret = -EINVAL;
+			goto out;
+		}
+
+		ret = i2c_smbus_read_word_data(chip->client, reg);
+		if (ret < 0)
+			goto out;
+		/* 1 + gain_val / 2^16 */
+		*val = 1;
+		*val2 = (15625 * swab16(ret)) / 1024;
+
+		ret = IIO_VAL_INT_PLUS_MICRO;
+		break;
+	case (1 << IIO_CHAN_INFO_CALIBBIAS_SHARED):
+		ret = i2c_smbus_read_word_data(chip->client,
+					       AD7746_REG_CAP_OFFH);
+		if (ret < 0)
+			goto out;
+		*val = swab16(ret);
+
+		ret = IIO_VAL_INT;
+		break;
+	case (1 << IIO_CHAN_INFO_OFFSET_SEPARATE):
+		*val = AD7746_CAPDAC_DACP(chip->capdac[chan->channel]
+			[chan->differential]) * 346773;
+
+		ret = IIO_VAL_INT;
+		break;
+	case (1 << IIO_CHAN_INFO_SCALE_SHARED):
+		switch (chan->type) {
+		case IIO_CAPACITANCE:
+			/* 8pf / 2^24 */
+			*val2 = 477;
+			*val =  0;
+			break;
+		case IIO_VOLTAGE:
+			/* 1170mV / 2^23 */
+			*val2 = 139475;
+			*val =  0;
+			break;
+		default:
+			ret =  -EINVAL;
+			goto out;
+		}
+
+		ret = IIO_VAL_INT_PLUS_NANO;
+		break;
+	default:
+		ret = -EINVAL;
+	};
+out:
+	mutex_unlock(&indio_dev->mlock);
+	return ret;
+}
+
+static const struct iio_info ad7746_info = {
+	.attrs = &ad7746_attribute_group,
+	.read_raw = &ad7746_read_raw,
+	.write_raw = &ad7746_write_raw,
+	.driver_module = THIS_MODULE,
+};
+
+/*
+ * device probe and remove
+ */
+
+static int __devinit ad7746_probe(struct i2c_client *client,
+		const struct i2c_device_id *id)
+{
+	struct ad7746_platform_data *pdata = client->dev.platform_data;
+	struct ad7746_chip_info *chip;
+	struct iio_dev *indio_dev;
+	int ret = 0;
+	unsigned char regval = 0;
+
+	indio_dev = iio_allocate_device(sizeof(*chip));
+	if (indio_dev == NULL) {
+		ret = -ENOMEM;
+		goto error_ret;
+	}
+	chip = iio_priv(indio_dev);
+	/* this is only used for device removal purposes */
+	i2c_set_clientdata(client, indio_dev);
+
+	chip->client = client;
+	chip->capdac_set = -1;
+
+	/* Establish that the iio_dev is a child of the i2c device */
+	indio_dev->name = id->name;
+	indio_dev->dev.parent = &client->dev;
+	indio_dev->info = &ad7746_info;
+	indio_dev->channels = ad7746_channels;
+	if (id->driver_data == 7746)
+		indio_dev->num_channels = ARRAY_SIZE(ad7746_channels);
+	else
+		indio_dev->num_channels =  ARRAY_SIZE(ad7746_channels) - 2;
+	indio_dev->num_channels = ARRAY_SIZE(ad7746_channels);
+	indio_dev->modes = INDIO_DIRECT_MODE;
+
+	if (pdata) {
+		if (pdata->exca_en) {
+			if (pdata->exca_inv_en)
+				regval |= AD7746_EXCSETUP_NEXCA;
+			else
+				regval |= AD7746_EXCSETUP_EXCA;
+		}
+
+		if (pdata->excb_en) {
+			if (pdata->excb_inv_en)
+				regval |= AD7746_EXCSETUP_NEXCB;
+			else
+				regval |= AD7746_EXCSETUP_EXCB;
+		}
+
+		regval |= AD7746_EXCSETUP_EXCLVL(pdata->exclvl);
+	} else {
+		dev_warn(&client->dev, "No platform data? using default\n");
+		regval = AD7746_EXCSETUP_EXCA | AD7746_EXCSETUP_EXCB |
+			AD7746_EXCSETUP_EXCLVL(3);
+	}
+
+	ret = i2c_smbus_write_byte_data(chip->client,
+					AD7746_REG_EXC_SETUP, regval);
+	if (ret < 0)
+		goto error_free_dev;
+
+	ret = iio_device_register(indio_dev);
+	if (ret)
+		goto error_free_dev;
+
+	dev_info(&client->dev, "%s capacitive sensor registered\n", id->name);
+
+	return 0;
+
+error_free_dev:
+	iio_free_device(indio_dev);
+error_ret:
+	return ret;
+}
+
+static int __devexit ad7746_remove(struct i2c_client *client)
+{
+	struct iio_dev *indio_dev = i2c_get_clientdata(client);
+
+	iio_device_unregister(indio_dev);
+
+	return 0;
+}
+
+static const struct i2c_device_id ad7746_id[] = {
+	{ "ad7745", 7745 },
+	{ "ad7746", 7746 },
+	{ "ad7747", 7747 },
+	{}
+};
+
+MODULE_DEVICE_TABLE(i2c, ad7746_id);
+
+static struct i2c_driver ad7746_driver = {
+	.driver = {
+		.name = KBUILD_MODNAME,
+	},
+	.probe = ad7746_probe,
+	.remove = __devexit_p(ad7746_remove),
+	.id_table = ad7746_id,
+};
+
+static __init int ad7746_init(void)
+{
+	return i2c_add_driver(&ad7746_driver);
+}
+
+static __exit void ad7746_exit(void)
+{
+	i2c_del_driver(&ad7746_driver);
+}
+
+MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
+MODULE_DESCRIPTION("Analog Devices AD7746/5/7 capacitive sensor driver");
+MODULE_LICENSE("GPL v2");
+
+module_init(ad7746_init);
+module_exit(ad7746_exit);
diff --git a/drivers/staging/iio/adc/ad7746.h b/drivers/staging/iio/adc/ad7746.h
new file mode 100644
index 0000000..ea8572d
--- /dev/null
+++ b/drivers/staging/iio/adc/ad7746.h
@@ -0,0 +1,29 @@
+/*
+ * AD7746 capacitive sensor driver supporting AD7745, AD7746 and AD7747
+ *
+ * Copyright 2011 Analog Devices Inc.
+ *
+ * Licensed under the GPL-2.
+ */
+
+#ifndef IIO_CDC_AD7746_H_
+#define IIO_CDC_AD7746_H_
+
+/*
+ * TODO: struct ad7746_platform_data needs to go into include/linux/iio
+ */
+
+#define AD7466_EXCLVL_0		0 /* +-VDD/8 */
+#define AD7466_EXCLVL_1		1 /* +-VDD/4 */
+#define AD7466_EXCLVL_2		2 /* +-VDD * 3/8 */
+#define AD7466_EXCLVL_3		3 /* +-VDD/2 */
+
+struct ad7746_platform_data {
+	unsigned char exclvl;	/*Excitation Voltage Level */
+	bool exca_en;		/* enables EXCA pin as the excitation output */
+	bool exca_inv_en;	/* enables /EXCA pin as the excitation output */
+	bool excb_en;		/* enables EXCB pin as the excitation output */
+	bool excb_inv_en;	/* enables /EXCB pin as the excitation output */
+};
+
+#endif /* IIO_CDC_AD7746_H_ */
-- 
1.7.0.4

^ permalink raw reply related	[flat|nested] 6+ messages in thread

* [PATCH] iio: adc: Replace, rewrite ad7745 from scratch.
@ 2011-09-16 14:47 michael.hennerich
  2011-09-19 12:19 ` Jonathan Cameron
  0 siblings, 1 reply; 6+ messages in thread
From: michael.hennerich @ 2011-09-16 14:47 UTC (permalink / raw)
  To: jic23; +Cc: linux-iio, device-drivers-devel, drivers, Michael Hennerich

From: Michael Hennerich <michael.hennerich@analog.com>

The existing ad7745 driver didn't conform with the IIO spec for such devices.
It was way simpler to rewrite the existing driver, than actually fixing it.

Changes since V1:

Fix file header description.
Fix erroneous defines.
Pin channels to expected places in the iio_chan_spec array, to avoid magic numbers.
Use msleep instead of busy waiting mdelay.
Fix indention style.
Drop _bias and use _offset attribute.

Changes since V2:
Increase accuracy of cap scale.
Fix channel spec for VIN.

Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
---
 drivers/staging/iio/adc/Kconfig  |    2 +-
 drivers/staging/iio/adc/Makefile |    2 +-
 drivers/staging/iio/adc/ad7745.c |  672 --------------------------------
 drivers/staging/iio/adc/ad7746.c |  800 ++++++++++++++++++++++++++++++++++++++
 drivers/staging/iio/adc/ad7746.h |   29 ++
 5 files changed, 831 insertions(+), 674 deletions(-)
 delete mode 100644 drivers/staging/iio/adc/ad7745.c
 create mode 100644 drivers/staging/iio/adc/ad7746.c
 create mode 100644 drivers/staging/iio/adc/ad7746.h

diff --git a/drivers/staging/iio/adc/Kconfig b/drivers/staging/iio/adc/Kconfig
index 7867ab1..0482073 100644
--- a/drivers/staging/iio/adc/Kconfig
+++ b/drivers/staging/iio/adc/Kconfig
@@ -144,7 +144,7 @@ config AD7793
 	  To compile this driver as a module, choose M here: the
 	  module will be called AD7793.
 
-config AD7745
+config AD7746
 	tristate "Analog Devices AD7745, AD7746 AD7747 capacitive sensor driver"
 	depends on I2C
 	help
diff --git a/drivers/staging/iio/adc/Makefile b/drivers/staging/iio/adc/Makefile
index 990d3fa..5ba3cdb 100644
--- a/drivers/staging/iio/adc/Makefile
+++ b/drivers/staging/iio/adc/Makefile
@@ -33,7 +33,7 @@ obj-$(CONFIG_AD7150) += ad7150.o
 obj-$(CONFIG_AD7152) += ad7152.o
 obj-$(CONFIG_AD7291) += ad7291.o
 obj-$(CONFIG_AD7314) += ad7314.o
-obj-$(CONFIG_AD7745) += ad7745.o
+obj-$(CONFIG_AD7746) += ad7746.o
 obj-$(CONFIG_AD7780) += ad7780.o
 obj-$(CONFIG_AD7793) += ad7793.o
 obj-$(CONFIG_AD7816) += ad7816.o
diff --git a/drivers/staging/iio/adc/ad7745.c b/drivers/staging/iio/adc/ad7745.c
deleted file mode 100644
index 4739593..0000000
--- a/drivers/staging/iio/adc/ad7745.c
+++ /dev/null
@@ -1,672 +0,0 @@
-/*
- * AD774X capacitive sensor driver supporting AD7745/6/7
- *
- * Copyright 2010 Analog Devices Inc.
- *
- * Licensed under the GPL-2 or later.
- */
-
-#include <linux/interrupt.h>
-#include <linux/gpio.h>
-#include <linux/device.h>
-#include <linux/kernel.h>
-#include <linux/slab.h>
-#include <linux/sysfs.h>
-#include <linux/list.h>
-#include <linux/i2c.h>
-
-#include "../iio.h"
-#include "../sysfs.h"
-
-/*
- * AD774X registers definition
- */
-
-#define AD774X_STATUS		0
-#define AD774X_STATUS_RDY	(1 << 2)
-#define AD774X_STATUS_RDYVT	(1 << 1)
-#define AD774X_STATUS_RDYCAP	(1 << 0)
-#define AD774X_CAP_DATA_HIGH	1
-#define AD774X_CAP_DATA_MID	2
-#define AD774X_CAP_DATA_LOW	3
-#define AD774X_VT_DATA_HIGH	4
-#define AD774X_VT_DATA_MID	5
-#define AD774X_VT_DATA_LOW	6
-#define AD774X_CAP_SETUP	7
-#define AD774X_VT_SETUP		8
-#define AD774X_EXEC_SETUP	9
-#define AD774X_CFG		10
-#define AD774X_CAPDACA		11
-#define AD774X_CAPDACB		12
-#define AD774X_CAPDAC_EN	(1 << 7)
-#define AD774X_CAP_OFFH		13
-#define AD774X_CAP_OFFL		14
-#define AD774X_CAP_GAINH	15
-#define AD774X_CAP_GAINL	16
-#define AD774X_VOLT_GAINH	17
-#define AD774X_VOLT_GAINL	18
-
-#define AD774X_MAX_CONV_MODE	6
-
-/*
- * struct ad774x_chip_info - chip specifc information
- */
-
-struct ad774x_chip_info {
-	struct i2c_client *client;
-	bool inter;
-	u16 cap_offs;                   /* Capacitive offset */
-	u16 cap_gain;                   /* Capacitive gain calibration */
-	u16 volt_gain;                  /* Voltage gain calibration */
-	u8  cap_setup;
-	u8  vt_setup;
-	u8  exec_setup;
-
-	char *conversion_mode;
-};
-
-struct ad774x_conversion_mode {
-	char *name;
-	u8 reg_cfg;
-};
-
-static struct ad774x_conversion_mode
-ad774x_conv_mode_table[AD774X_MAX_CONV_MODE] = {
-	{ "idle", 0 },
-	{ "continuous-conversion", 1 },
-	{ "single-conversion", 2 },
-	{ "power-down", 3 },
-	{ "offset-calibration", 5 },
-	{ "gain-calibration", 6 },
-};
-
-/*
- * ad774x register access by I2C
- */
-
-static int ad774x_i2c_read(struct ad774x_chip_info *chip, u8 reg, u8 *data, int len)
-{
-	struct i2c_client *client = chip->client;
-	int ret;
-
-	ret = i2c_master_send(client, &reg, 1);
-	if (ret < 0) {
-		dev_err(&client->dev, "I2C write error\n");
-		return ret;
-	}
-
-	ret = i2c_master_recv(client, data, len);
-	if (ret < 0) {
-		dev_err(&client->dev, "I2C read error\n");
-		return ret;
-	}
-
-	return ret;
-}
-
-static int ad774x_i2c_write(struct ad774x_chip_info *chip, u8 reg, u8 data)
-{
-	struct i2c_client *client = chip->client;
-	int ret;
-
-	u8 tx[2] = {
-		reg,
-		data,
-	};
-
-	ret = i2c_master_send(client, tx, 2);
-	if (ret < 0)
-		dev_err(&client->dev, "I2C write error\n");
-
-	return ret;
-}
-
-/*
- * sysfs nodes
- */
-
-#define IIO_DEV_ATTR_AVAIL_CONVERSION_MODES(_show)				\
-	IIO_DEVICE_ATTR(available_conversion_modes, S_IRUGO, _show, NULL, 0)
-#define IIO_DEV_ATTR_CONVERSION_MODE(_mode, _show, _store)              \
-	IIO_DEVICE_ATTR(conversion_mode, _mode, _show, _store, 0)
-#define IIO_DEV_ATTR_CAP_SETUP(_mode, _show, _store)		\
-	IIO_DEVICE_ATTR(cap_setup, _mode, _show, _store, 0)
-#define IIO_DEV_ATTR_VT_SETUP(_mode, _show, _store)              \
-	IIO_DEVICE_ATTR(in0_setup, _mode, _show, _store, 0)
-#define IIO_DEV_ATTR_EXEC_SETUP(_mode, _show, _store)              \
-	IIO_DEVICE_ATTR(exec_setup, _mode, _show, _store, 0)
-#define IIO_DEV_ATTR_VOLT_GAIN(_mode, _show, _store)		\
-	IIO_DEVICE_ATTR(in0_gain, _mode, _show, _store, 0)
-#define IIO_DEV_ATTR_CAP_OFFS(_mode, _show, _store)		\
-	IIO_DEVICE_ATTR(cap_offs, _mode, _show, _store, 0)
-#define IIO_DEV_ATTR_CAP_GAIN(_mode, _show, _store)		\
-	IIO_DEVICE_ATTR(cap_gain, _mode, _show, _store, 0)
-#define IIO_DEV_ATTR_CAP_DATA(_show)		\
-	IIO_DEVICE_ATTR(cap0_raw, S_IRUGO, _show, NULL, 0)
-#define IIO_DEV_ATTR_VT_DATA(_show)		\
-	IIO_DEVICE_ATTR(in0_raw, S_IRUGO, _show, NULL, 0)
-
-static ssize_t ad774x_show_conversion_modes(struct device *dev,
-		struct device_attribute *attr,
-		char *buf)
-{
-	int i;
-	int len = 0;
-
-	for (i = 0; i < AD774X_MAX_CONV_MODE; i++)
-		len += sprintf(buf + len, "%s ", ad774x_conv_mode_table[i].name);
-
-	len += sprintf(buf + len, "\n");
-
-	return len;
-}
-
-static IIO_DEV_ATTR_AVAIL_CONVERSION_MODES(ad774x_show_conversion_modes);
-
-static ssize_t ad774x_show_conversion_mode(struct device *dev,
-		struct device_attribute *attr,
-		char *buf)
-{
-	struct iio_dev *dev_info = dev_get_drvdata(dev);
-	struct ad774x_chip_info *chip = iio_priv(dev_info);
-
-	return sprintf(buf, "%s\n", chip->conversion_mode);
-}
-
-static ssize_t ad774x_store_conversion_mode(struct device *dev,
-		struct device_attribute *attr,
-		const char *buf,
-		size_t len)
-{
-	struct iio_dev *dev_info = dev_get_drvdata(dev);
-	struct ad774x_chip_info *chip = iio_priv(dev_info);
-	u8 cfg;
-	int i;
-
-	ad774x_i2c_read(chip, AD774X_CFG, &cfg, 1);
-
-	for (i = 0; i < AD774X_MAX_CONV_MODE; i++) {
-		if (strncmp(buf, ad774x_conv_mode_table[i].name,
-				strlen(ad774x_conv_mode_table[i].name) - 1) == 0) {
-			chip->conversion_mode = ad774x_conv_mode_table[i].name;
-			cfg |= 0x18 | ad774x_conv_mode_table[i].reg_cfg;
-			ad774x_i2c_write(chip, AD774X_CFG, cfg);
-			return len;
-		}
-	}
-
-	dev_err(dev, "not supported conversion mode\n");
-
-	return -EINVAL;
-}
-
-static IIO_DEV_ATTR_CONVERSION_MODE(S_IRUGO | S_IWUSR,
-		ad774x_show_conversion_mode,
-		ad774x_store_conversion_mode);
-
-static ssize_t ad774x_show_dac_value(struct device *dev,
-		struct device_attribute *attr,
-		char *buf)
-{
-	struct iio_dev *dev_info = dev_get_drvdata(dev);
-	struct ad774x_chip_info *chip = iio_priv(dev_info);
-	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
-	u8 data;
-
-	ad774x_i2c_read(chip, this_attr->address, &data, 1);
-
-	return sprintf(buf, "%02x\n", data & 0x7F);
-}
-
-static ssize_t ad774x_store_dac_value(struct device *dev,
-		struct device_attribute *attr,
-		const char *buf,
-		size_t len)
-{
-	struct iio_dev *dev_info = dev_get_drvdata(dev);
-	struct ad774x_chip_info *chip = iio_priv(dev_info);
-	struct iio_dev_attr *this_attr = to_iio_dev_attr(attr);
-	unsigned long data;
-	int ret;
-
-	ret = strict_strtoul(buf, 10, &data);
-
-	if (!ret) {
-		ad774x_i2c_write(chip, this_attr->address,
-			(data ? AD774X_CAPDAC_EN : 0) | (data & 0x7F));
-		return len;
-	}
-
-	return -EINVAL;
-}
-
-static IIO_DEVICE_ATTR(capdac0_raw, S_IRUGO | S_IWUSR,
-			ad774x_show_dac_value,
-			ad774x_store_dac_value,
-			AD774X_CAPDACA);
-
-static IIO_DEVICE_ATTR(capdac1_raw, S_IRUGO | S_IWUSR,
-			ad774x_show_dac_value,
-			ad774x_store_dac_value,
-			AD774X_CAPDACB);
-
-static ssize_t ad774x_show_cap_setup(struct device *dev,
-		struct device_attribute *attr,
-		char *buf)
-{
-	struct iio_dev *dev_info = dev_get_drvdata(dev);
-	struct ad774x_chip_info *chip = iio_priv(dev_info);
-
-	return sprintf(buf, "0x%02x\n", chip->cap_setup);
-}
-
-static ssize_t ad774x_store_cap_setup(struct device *dev,
-		struct device_attribute *attr,
-		const char *buf,
-		size_t len)
-{
-	struct iio_dev *dev_info = dev_get_drvdata(dev);
-	struct ad774x_chip_info *chip = iio_priv(dev_info);
-	unsigned long data;
-	int ret;
-
-	ret = strict_strtoul(buf, 10, &data);
-
-	if ((!ret) && (data < 0x100)) {
-		ad774x_i2c_write(chip, AD774X_CAP_SETUP, data);
-		chip->cap_setup = data;
-		return len;
-	}
-
-	return -EINVAL;
-}
-
-static IIO_DEV_ATTR_CAP_SETUP(S_IRUGO | S_IWUSR,
-		ad774x_show_cap_setup,
-		ad774x_store_cap_setup);
-
-static ssize_t ad774x_show_vt_setup(struct device *dev,
-		struct device_attribute *attr,
-		char *buf)
-{
-	struct iio_dev *dev_info = dev_get_drvdata(dev);
-	struct ad774x_chip_info *chip = iio_priv(dev_info);
-
-	return sprintf(buf, "0x%02x\n", chip->vt_setup);
-}
-
-static ssize_t ad774x_store_vt_setup(struct device *dev,
-		struct device_attribute *attr,
-		const char *buf,
-		size_t len)
-{
-	struct iio_dev *dev_info = dev_get_drvdata(dev);
-	struct ad774x_chip_info *chip = iio_priv(dev_info);
-	unsigned long data;
-	int ret;
-
-	ret = strict_strtoul(buf, 10, &data);
-
-	if ((!ret) && (data < 0x100)) {
-		ad774x_i2c_write(chip, AD774X_VT_SETUP, data);
-		chip->vt_setup = data;
-		return len;
-	}
-
-	return -EINVAL;
-}
-
-static IIO_DEV_ATTR_VT_SETUP(S_IRUGO | S_IWUSR,
-		ad774x_show_vt_setup,
-		ad774x_store_vt_setup);
-
-static ssize_t ad774x_show_exec_setup(struct device *dev,
-		struct device_attribute *attr,
-		char *buf)
-{
-	struct iio_dev *dev_info = dev_get_drvdata(dev);
-	struct ad774x_chip_info *chip = iio_priv(dev_info);
-
-	return sprintf(buf, "0x%02x\n", chip->exec_setup);
-}
-
-static ssize_t ad774x_store_exec_setup(struct device *dev,
-		struct device_attribute *attr,
-		const char *buf,
-		size_t len)
-{
-	struct iio_dev *dev_info = dev_get_drvdata(dev);
-	struct ad774x_chip_info *chip = iio_priv(dev_info);
-	unsigned long data;
-	int ret;
-
-	ret = strict_strtoul(buf, 10, &data);
-
-	if ((!ret) && (data < 0x100)) {
-		ad774x_i2c_write(chip, AD774X_EXEC_SETUP, data);
-		chip->exec_setup = data;
-		return len;
-	}
-
-	return -EINVAL;
-}
-
-static IIO_DEV_ATTR_EXEC_SETUP(S_IRUGO | S_IWUSR,
-		ad774x_show_exec_setup,
-		ad774x_store_exec_setup);
-
-static ssize_t ad774x_show_volt_gain(struct device *dev,
-		struct device_attribute *attr,
-		char *buf)
-{
-	struct iio_dev *dev_info = dev_get_drvdata(dev);
-	struct ad774x_chip_info *chip = iio_priv(dev_info);
-
-	return sprintf(buf, "%d\n", chip->volt_gain);
-}
-
-static ssize_t ad774x_store_volt_gain(struct device *dev,
-		struct device_attribute *attr,
-		const char *buf,
-		size_t len)
-{
-	struct iio_dev *dev_info = dev_get_drvdata(dev);
-	struct ad774x_chip_info *chip = iio_priv(dev_info);
-	unsigned long data;
-	int ret;
-
-	ret = strict_strtoul(buf, 10, &data);
-
-	if ((!ret) && (data < 0x10000)) {
-		ad774x_i2c_write(chip, AD774X_VOLT_GAINH, data >> 8);
-		ad774x_i2c_write(chip, AD774X_VOLT_GAINL, data);
-		chip->volt_gain = data;
-		return len;
-	}
-
-	return -EINVAL;
-}
-
-static IIO_DEV_ATTR_VOLT_GAIN(S_IRUGO | S_IWUSR,
-		ad774x_show_volt_gain,
-		ad774x_store_volt_gain);
-
-static ssize_t ad774x_show_cap_data(struct device *dev,
-		struct device_attribute *attr,
-		char *buf)
-{
-	struct iio_dev *dev_info = dev_get_drvdata(dev);
-	struct ad774x_chip_info *chip = iio_priv(dev_info);
-	unsigned long data;
-	char tmp[3];
-
-	ad774x_i2c_read(chip, AD774X_CAP_DATA_HIGH, tmp, 3);
-	data = ((int)tmp[0] << 16) | ((int)tmp[1] << 8) | (int)tmp[2];
-
-	return sprintf(buf, "%ld\n", data);
-}
-
-static IIO_DEV_ATTR_CAP_DATA(ad774x_show_cap_data);
-
-static ssize_t ad774x_show_vt_data(struct device *dev,
-		struct device_attribute *attr,
-		char *buf)
-{
-	struct iio_dev *dev_info = dev_get_drvdata(dev);
-	struct ad774x_chip_info *chip = iio_priv(dev_info);
-	unsigned long data;
-	char tmp[3];
-
-	ad774x_i2c_read(chip, AD774X_VT_DATA_HIGH, tmp, 3);
-	data = ((int)tmp[0] << 16) | ((int)tmp[1] << 8) | (int)tmp[2];
-
-	return sprintf(buf, "%ld\n", data);
-}
-
-static IIO_DEV_ATTR_VT_DATA(ad774x_show_vt_data);
-
-static ssize_t ad774x_show_cap_offs(struct device *dev,
-		struct device_attribute *attr,
-		char *buf)
-{
-	struct iio_dev *dev_info = dev_get_drvdata(dev);
-	struct ad774x_chip_info *chip = iio_priv(dev_info);
-
-	return sprintf(buf, "%d\n", chip->cap_offs);
-}
-
-static ssize_t ad774x_store_cap_offs(struct device *dev,
-		struct device_attribute *attr,
-		const char *buf,
-		size_t len)
-{
-	struct iio_dev *dev_info = dev_get_drvdata(dev);
-	struct ad774x_chip_info *chip = iio_priv(dev_info);
-	unsigned long data;
-	int ret;
-
-	ret = strict_strtoul(buf, 10, &data);
-
-	if ((!ret) && (data < 0x10000)) {
-		ad774x_i2c_write(chip, AD774X_CAP_OFFH, data >> 8);
-		ad774x_i2c_write(chip, AD774X_CAP_OFFL, data);
-		chip->cap_offs = data;
-		return len;
-	}
-
-	return -EINVAL;
-}
-
-static IIO_DEV_ATTR_CAP_OFFS(S_IRUGO | S_IWUSR,
-		ad774x_show_cap_offs,
-		ad774x_store_cap_offs);
-
-static ssize_t ad774x_show_cap_gain(struct device *dev,
-		struct device_attribute *attr,
-		char *buf)
-{
-	struct iio_dev *dev_info = dev_get_drvdata(dev);
-	struct ad774x_chip_info *chip = iio_priv(dev_info);
-
-	return sprintf(buf, "%d\n", chip->cap_gain);
-}
-
-static ssize_t ad774x_store_cap_gain(struct device *dev,
-		struct device_attribute *attr,
-		const char *buf,
-		size_t len)
-{
-	struct iio_dev *dev_info = dev_get_drvdata(dev);
-	struct ad774x_chip_info *chip = iio_priv(dev_info);
-	unsigned long data;
-	int ret;
-
-	ret = strict_strtoul(buf, 10, &data);
-
-	if ((!ret) && (data < 0x10000)) {
-		ad774x_i2c_write(chip, AD774X_CAP_GAINH, data >> 8);
-		ad774x_i2c_write(chip, AD774X_CAP_GAINL, data);
-		chip->cap_gain = data;
-		return len;
-	}
-
-	return -EINVAL;
-}
-
-static IIO_DEV_ATTR_CAP_GAIN(S_IRUGO | S_IWUSR,
-		ad774x_show_cap_gain,
-		ad774x_store_cap_gain);
-
-static struct attribute *ad774x_attributes[] = {
-	&iio_dev_attr_available_conversion_modes.dev_attr.attr,
-	&iio_dev_attr_conversion_mode.dev_attr.attr,
-	&iio_dev_attr_cap_setup.dev_attr.attr,
-	&iio_dev_attr_in0_setup.dev_attr.attr,
-	&iio_dev_attr_exec_setup.dev_attr.attr,
-	&iio_dev_attr_cap_offs.dev_attr.attr,
-	&iio_dev_attr_cap_gain.dev_attr.attr,
-	&iio_dev_attr_in0_gain.dev_attr.attr,
-	&iio_dev_attr_in0_raw.dev_attr.attr,
-	&iio_dev_attr_cap0_raw.dev_attr.attr,
-	&iio_dev_attr_capdac0_raw.dev_attr.attr,
-	&iio_dev_attr_capdac1_raw.dev_attr.attr,
-	NULL,
-};
-
-static const struct attribute_group ad774x_attribute_group = {
-	.attrs = ad774x_attributes,
-};
-
-/*
- * data ready events
- */
-
-#define IIO_EVENT_CODE_CAP_RDY     0
-#define IIO_EVENT_CODE_VT_RDY      1
-
-#define IIO_EVENT_ATTR_CAP_RDY_SH(_evlist, _show, _store, _mask)	\
-	IIO_EVENT_ATTR_SH(cap_rdy, _evlist, _show, _store, _mask)
-
-#define IIO_EVENT_ATTR_VT_RDY_SH(_evlist, _show, _store, _mask)	\
-	IIO_EVENT_ATTR_SH(vt_rdy, _evlist, _show, _store, _mask)
-
-static irqreturn_t ad774x_event_handler(int irq, void *private)
-{
-	struct iio_dev *indio_dev = private;
-	struct ad774x_chip_info *chip = iio_priv(indio_dev);
-	u8 int_status;
-
-	ad774x_i2c_read(chip, AD774X_STATUS, &int_status, 1);
-
-	if (int_status & AD774X_STATUS_RDYCAP)
-		iio_push_event(indio_dev,
-			       IIO_EVENT_CODE_CAP_RDY,
-			       iio_get_time_ns());
-
-	if (int_status & AD774X_STATUS_RDYVT)
-		iio_push_event(indio_dev,
-			       IIO_EVENT_CODE_VT_RDY,
-			       iio_get_time_ns());
-
-	return IRQ_HANDLED;
-}
-
-static IIO_CONST_ATTR(cap_rdy_en, "1");
-static IIO_CONST_ATTR(vt_rdy_en, "1");
-
-static struct attribute *ad774x_event_attributes[] = {
-	&iio_const_attr_cap_rdy_en.dev_attr.attr,
-	&iio_const_attr_vt_rdy_en.dev_attr.attr,
-	NULL,
-};
-
-static struct attribute_group ad774x_event_attribute_group = {
-	.attrs = ad774x_event_attributes,
-	.name = "events",
-};
-
-static const struct iio_info ad774x_info = {
-	.attrs = &ad774x_event_attribute_group,
-	.event_attrs = &ad774x_event_attribute_group,
-	.driver_module = THIS_MODULE,
-};
-/*
- * device probe and remove
- */
-
-static int __devinit ad774x_probe(struct i2c_client *client,
-		const struct i2c_device_id *id)
-{
-	int ret;
-	struct ad774x_chip_info *chip;
-	struct iio_dev *indio_dev;
-
-	indio_dev = iio_allocate_device(sizeof(*chip));
-	if (indio_dev == NULL) {
-		ret = -ENOMEM;
-		goto error_ret;
-	}
-	chip = iio_priv(indio_dev);
-	/* this is only used for device removal purposes */
-	i2c_set_clientdata(client, indio_dev);
-
-	chip->client = client;
-
-	/* Establish that the iio_dev is a child of the i2c device */
-	indio_dev->name = id->name;
-	indio_dev->dev.parent = &client->dev;
-	indio_dev->info = &ad774x_info;
-	indio_dev->modes = INDIO_DIRECT_MODE;
-
-	if (client->irq) {
-		ret = request_threaded_irq(client->irq,
-					   NULL,
-					   &ad774x_event_handler,
-					   IRQF_TRIGGER_FALLING,
-					   "ad774x",
-					   indio_dev);
-		if (ret)
-			goto error_free_dev;
-	}
-
-	ret = iio_device_register(indio_dev);
-	if (ret)
-		goto error_free_irq;
-
-	dev_err(&client->dev, "%s capacitive sensor registered, irq: %d\n", id->name, client->irq);
-
-	return 0;
-
-error_free_irq:
-	free_irq(client->irq, indio_dev);
-error_free_dev:
-	iio_free_device(indio_dev);
-error_ret:
-	return ret;
-}
-
-static int __devexit ad774x_remove(struct i2c_client *client)
-{
-	struct iio_dev *indio_dev = i2c_get_clientdata(client);
-
-	if (client->irq)
-		free_irq(client->irq, indio_dev);
-	iio_device_unregister(indio_dev);
-
-	return 0;
-}
-
-static const struct i2c_device_id ad774x_id[] = {
-	{ "ad7745", 0 },
-	{ "ad7746", 0 },
-	{ "ad7747", 0 },
-	{}
-};
-
-MODULE_DEVICE_TABLE(i2c, ad774x_id);
-
-static struct i2c_driver ad774x_driver = {
-	.driver = {
-		.name = "ad774x",
-	},
-	.probe = ad774x_probe,
-	.remove = __devexit_p(ad774x_remove),
-	.id_table = ad774x_id,
-};
-
-static __init int ad774x_init(void)
-{
-	return i2c_add_driver(&ad774x_driver);
-}
-
-static __exit void ad774x_exit(void)
-{
-	i2c_del_driver(&ad774x_driver);
-}
-
-MODULE_AUTHOR("Barry Song <21cnbao@gmail.com>");
-MODULE_DESCRIPTION("Analog Devices ad7745/6/7 capacitive sensor driver");
-MODULE_LICENSE("GPL v2");
-
-module_init(ad774x_init);
-module_exit(ad774x_exit);
diff --git a/drivers/staging/iio/adc/ad7746.c b/drivers/staging/iio/adc/ad7746.c
new file mode 100644
index 0000000..b2011f5
--- /dev/null
+++ b/drivers/staging/iio/adc/ad7746.c
@@ -0,0 +1,800 @@
+/*
+ * AD7746 capacitive sensor driver supporting AD7745, AD7746 and AD7747
+ *
+ * Copyright 2011 Analog Devices Inc.
+ *
+ * Licensed under the GPL-2.
+ */
+
+#include <linux/interrupt.h>
+#include <linux/device.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/sysfs.h>
+#include <linux/i2c.h>
+#include <linux/delay.h>
+
+#include "../iio.h"
+#include "../sysfs.h"
+
+#include "ad7746.h"
+
+/*
+ * AD7746 Register Definition
+ */
+
+#define AD7746_REG_STATUS		0
+#define AD7746_REG_CAP_DATA_HIGH	1
+#define AD7746_REG_CAP_DATA_MID		2
+#define AD7746_REG_CAP_DATA_LOW		3
+#define AD7746_REG_VT_DATA_HIGH		4
+#define AD7746_REG_VT_DATA_MID		5
+#define AD7746_REG_VT_DATA_LOW		6
+#define AD7746_REG_CAP_SETUP		7
+#define AD7746_REG_VT_SETUP		8
+#define AD7746_REG_EXC_SETUP		9
+#define AD7746_REG_CFG			10
+#define AD7746_REG_CAPDACA		11
+#define AD7746_REG_CAPDACB		12
+#define AD7746_REG_CAP_OFFH		13
+#define AD7746_REG_CAP_OFFL		14
+#define AD7746_REG_CAP_GAINH		15
+#define AD7746_REG_CAP_GAINL		16
+#define AD7746_REG_VOLT_GAINH		17
+#define AD7746_REG_VOLT_GAINL		18
+
+/* Status Register Bit Designations (AD7746_REG_STATUS) */
+#define AD7746_STATUS_EXCERR		(1 << 3)
+#define AD7746_STATUS_RDY		(1 << 2)
+#define AD7746_STATUS_RDYVT		(1 << 1)
+#define AD7746_STATUS_RDYCAP		(1 << 0)
+
+/* Capacitive Channel Setup Register Bit Designations (AD7746_REG_CAP_SETUP) */
+#define AD7746_CAPSETUP_CAPEN		(1 << 7)
+#define AD7746_CAPSETUP_CIN2		(1 << 6) /* AD7746 only */
+#define AD7746_CAPSETUP_CAPDIFF		(1 << 5)
+#define AD7746_CAPSETUP_CACHOP		(1 << 0)
+
+/* Voltage/Temperature Setup Register Bit Designations (AD7746_REG_VT_SETUP) */
+#define AD7746_VTSETUP_VTEN		(1 << 7)
+#define AD7746_VTSETUP_VTMD_INT_TEMP	(0 << 5)
+#define AD7746_VTSETUP_VTMD_EXT_TEMP	(1 << 5)
+#define AD7746_VTSETUP_VTMD_VDD_MON	(2 << 5)
+#define AD7746_VTSETUP_VTMD_EXT_VIN	(3 << 5)
+#define AD7746_VTSETUP_EXTREF		(1 << 4)
+#define AD7746_VTSETUP_VTSHORT		(1 << 1)
+#define AD7746_VTSETUP_VTCHOP		(1 << 0)
+
+/* Excitation Setup Register Bit Designations (AD7746_REG_EXC_SETUP) */
+#define AD7746_EXCSETUP_CLKCTRL		(1 << 7)
+#define AD7746_EXCSETUP_EXCON		(1 << 6)
+#define AD7746_EXCSETUP_EXCB		(1 << 5)
+#define AD7746_EXCSETUP_NEXCB		(1 << 4)
+#define AD7746_EXCSETUP_EXCA		(1 << 3)
+#define AD7746_EXCSETUP_NEXCA		(1 << 2)
+#define AD7746_EXCSETUP_EXCLVL(x)	(((x) & 0x3) << 0)
+
+/* Config Register Bit Designations (AD7746_REG_CFG) */
+#define AD7746_CONF_VTFS(x)		((x) << 6)
+#define AD7746_CONF_CAPFS(x)		((x) << 3)
+#define AD7746_CONF_MODE_IDLE		(0 << 0)
+#define AD7746_CONF_MODE_CONT_CONV	(1 << 0)
+#define AD7746_CONF_MODE_SINGLE_CONV	(2 << 0)
+#define AD7746_CONF_MODE_PWRDN		(3 << 0)
+#define AD7746_CONF_MODE_OFFS_CAL	(5 << 0)
+#define AD7746_CONF_MODE_GAIN_CAL	(6 << 0)
+
+/* CAPDAC Register Bit Designations (AD7746_REG_CAPDACx) */
+#define AD7746_CAPDAC_DACEN		(1 << 7)
+#define AD7746_CAPDAC_DACP(x)		((x) & 0x7F)
+
+/*
+ * struct ad7746_chip_info - chip specifc information
+ */
+
+struct ad7746_chip_info {
+	struct i2c_client *client;
+	/*
+	 * Capacitive channel digital filter setup;
+	 * conversion time/update rate setup per channel
+	 */
+	u8	config;
+	u8	cap_setup;
+	u8	vt_setup;
+	u8	capdac[2][2];
+	s8	capdac_set;
+};
+
+enum ad7746_chan {
+	VIN,
+	VIN_VDD,
+	TEMP_INT,
+	TEMP_EXT,
+	CIN1,
+	CIN1_DIFF,
+	CIN2,
+	CIN2_DIFF,
+};
+
+static const struct iio_chan_spec ad7746_channels[] = {
+	[VIN] = {
+		.type = IIO_VOLTAGE,
+		.indexed = 1,
+		.channel = 0,
+		.info_mask = (1 << IIO_CHAN_INFO_SCALE_SHARED),
+		.address = AD7746_REG_VT_DATA_HIGH << 8 |
+			AD7746_VTSETUP_VTMD_EXT_VIN,
+	},
+	[VIN_VDD] = {
+		.type = IIO_VOLTAGE,
+		.indexed = 1,
+		.channel = 1,
+		.extend_name = "supply",
+		.info_mask = (1 << IIO_CHAN_INFO_SCALE_SHARED),
+		.address = AD7746_REG_VT_DATA_HIGH << 8 |
+			AD7746_VTSETUP_VTMD_VDD_MON,
+	},
+	[TEMP_INT] = {
+		.type = IIO_TEMP,
+		.indexed = 1,
+		.channel = 0,
+		.processed_val = IIO_PROCESSED,
+		.address = AD7746_REG_VT_DATA_HIGH << 8 |
+			AD7746_VTSETUP_VTMD_INT_TEMP,
+	},
+	[TEMP_EXT] = {
+		.type = IIO_TEMP,
+		.indexed = 1,
+		.channel = 1,
+		.processed_val = IIO_PROCESSED,
+		.address = AD7746_REG_VT_DATA_HIGH << 8 |
+			AD7746_VTSETUP_VTMD_EXT_TEMP,
+	},
+	[CIN1] = {
+		.type = IIO_CAPACITANCE,
+		.indexed = 1,
+		.channel = 0,
+		.info_mask = (1 << IIO_CHAN_INFO_CALIBSCALE_SEPARATE) |
+		(1 << IIO_CHAN_INFO_CALIBBIAS_SHARED) |
+		(1 << IIO_CHAN_INFO_OFFSET_SEPARATE) |
+		(1 << IIO_CHAN_INFO_SCALE_SHARED),
+		.address = AD7746_REG_CAP_DATA_HIGH << 8,
+	},
+	[CIN1_DIFF] = {
+		.type = IIO_CAPACITANCE,
+		.differential = 1,
+		.indexed = 1,
+		.channel = 0,
+		.channel2 = 2,
+		.info_mask = (1 << IIO_CHAN_INFO_CALIBSCALE_SEPARATE) |
+		(1 << IIO_CHAN_INFO_CALIBBIAS_SHARED) |
+		(1 << IIO_CHAN_INFO_OFFSET_SEPARATE) |
+		(1 << IIO_CHAN_INFO_SCALE_SHARED),
+		.address = AD7746_REG_CAP_DATA_HIGH << 8 |
+			AD7746_CAPSETUP_CAPDIFF
+	},
+	[CIN2] = {
+		.type = IIO_CAPACITANCE,
+		.indexed = 1,
+		.channel = 1,
+		.info_mask = (1 << IIO_CHAN_INFO_CALIBSCALE_SEPARATE) |
+		(1 << IIO_CHAN_INFO_CALIBBIAS_SHARED) |
+		(1 << IIO_CHAN_INFO_OFFSET_SEPARATE) |
+		(1 << IIO_CHAN_INFO_SCALE_SHARED),
+		.address = AD7746_REG_CAP_DATA_HIGH << 8 |
+			AD7746_CAPSETUP_CIN2,
+	},
+	[CIN2_DIFF] = {
+		.type = IIO_CAPACITANCE,
+		.differential = 1,
+		.indexed = 1,
+		.channel = 1,
+		.channel2 = 3,
+		.info_mask = (1 << IIO_CHAN_INFO_CALIBSCALE_SEPARATE) |
+		(1 << IIO_CHAN_INFO_CALIBBIAS_SHARED) |
+		(1 << IIO_CHAN_INFO_OFFSET_SEPARATE) |
+		(1 << IIO_CHAN_INFO_SCALE_SHARED),
+		.address = AD7746_REG_CAP_DATA_HIGH << 8 |
+			AD7746_CAPSETUP_CAPDIFF | AD7746_CAPSETUP_CIN2,
+	}
+};
+
+/* Values are Update Rate (Hz), Conversion Time (ms) + 1*/
+static const unsigned char ad7746_vt_filter_rate_table[][2] = {
+	{50, 20 + 1}, {31, 32 + 1}, {16, 62 + 1}, {8, 122 + 1},
+};
+
+static const unsigned char ad7746_cap_filter_rate_table[][2] = {
+	{91, 11 + 1}, {84, 12 + 1}, {50, 20 + 1}, {26, 38 + 1},
+	{16, 62 + 1}, {13, 77 + 1}, {11, 92 + 1}, {9, 110 + 1},
+};
+
+static int ad7746_select_channel(struct iio_dev *indio_dev,
+			    struct iio_chan_spec const *chan)
+{
+	struct ad7746_chip_info *chip = iio_priv(indio_dev);
+	int ret, delay;
+	u8 vt_setup, cap_setup;
+
+	switch (chan->type) {
+	case IIO_CAPACITANCE:
+		cap_setup = (chan->address & 0xFF) | AD7746_CAPSETUP_CAPEN;
+		vt_setup = chip->vt_setup & ~AD7746_VTSETUP_VTEN;
+		delay = ad7746_cap_filter_rate_table[(chip->config >> 3) &
+			0x7][1];
+
+		if (chip->capdac_set != chan->channel) {
+			ret = i2c_smbus_write_byte_data(chip->client,
+				AD7746_REG_CAPDACA,
+				chip->capdac[chan->channel][0]);
+			if (ret < 0)
+				return ret;
+			ret = i2c_smbus_write_byte_data(chip->client,
+				AD7746_REG_CAPDACB,
+				chip->capdac[chan->channel][1]);
+			if (ret < 0)
+				return ret;
+
+			chip->capdac_set = chan->channel;
+		}
+		break;
+	case IIO_VOLTAGE:
+	case IIO_TEMP:
+		vt_setup = (chan->address & 0xFF) | AD7746_VTSETUP_VTEN;
+		cap_setup = chip->cap_setup & ~AD7746_CAPSETUP_CAPEN;
+		delay = ad7746_cap_filter_rate_table[(chip->config >> 6) &
+			0x3][1];
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	if (chip->cap_setup != cap_setup) {
+		ret = i2c_smbus_write_byte_data(chip->client,
+						AD7746_REG_CAP_SETUP,
+						cap_setup);
+		if (ret < 0)
+			return ret;
+
+		chip->cap_setup = cap_setup;
+	}
+
+	if (chip->vt_setup != vt_setup) {
+		ret = i2c_smbus_write_byte_data(chip->client,
+						AD7746_REG_VT_SETUP,
+						vt_setup);
+		if (ret < 0)
+			return ret;
+
+		chip->vt_setup = vt_setup;
+	}
+
+	return delay;
+}
+
+static inline ssize_t ad7746_start_calib(struct device *dev,
+					 struct device_attribute *attr,
+					 const char *buf,
+					 size_t len,
+					 u8 regval)
+{
+	struct iio_dev *indio_dev = dev_get_drvdata(dev);
+	struct ad7746_chip_info *chip = iio_priv(indio_dev);
+	bool doit;
+	int ret, timeout = 10;
+
+	ret = strtobool(buf, &doit);
+	if (ret < 0)
+		return ret;
+
+	if (!doit)
+		return 0;
+
+	mutex_lock(&indio_dev->mlock);
+	regval |= chip->config;
+	ret = i2c_smbus_write_byte_data(chip->client, AD7746_REG_CFG, regval);
+	if (ret < 0) {
+		mutex_unlock(&indio_dev->mlock);
+		return ret;
+	}
+
+	do {
+		msleep(20);
+		ret = i2c_smbus_read_byte_data(chip->client, AD7746_REG_CFG);
+		if (ret < 0) {
+			mutex_unlock(&indio_dev->mlock);
+			return ret;
+		}
+	} while ((ret == regval) && timeout--);
+
+	mutex_unlock(&indio_dev->mlock);
+	return len;
+}
+static ssize_t ad7746_start_offset_calib(struct device *dev,
+					 struct device_attribute *attr,
+					 const char *buf,
+					 size_t len)
+{
+	struct iio_dev *indio_dev = dev_get_drvdata(dev);
+	int ret = ad7746_select_channel(indio_dev,
+			      &ad7746_channels[to_iio_dev_attr(attr)->address]);
+	if (ret < 0)
+		return ret;
+
+	return ad7746_start_calib(dev, attr, buf, len,
+				  AD7746_CONF_MODE_OFFS_CAL);
+}
+static ssize_t ad7746_start_gain_calib(struct device *dev,
+				       struct device_attribute *attr,
+				       const char *buf,
+				       size_t len)
+{
+	struct iio_dev *indio_dev = dev_get_drvdata(dev);
+	int ret = ad7746_select_channel(indio_dev,
+			      &ad7746_channels[to_iio_dev_attr(attr)->address]);
+	if (ret < 0)
+		return ret;
+
+	return ad7746_start_calib(dev, attr, buf, len,
+				  AD7746_CONF_MODE_GAIN_CAL);
+}
+
+static IIO_DEVICE_ATTR(in_capacitance0_calibbias_calibration,
+		       S_IWUSR, NULL, ad7746_start_offset_calib, CIN1);
+static IIO_DEVICE_ATTR(in_capacitance1_calibbias_calibration,
+		       S_IWUSR, NULL, ad7746_start_offset_calib, CIN2);
+static IIO_DEVICE_ATTR(in_capacitance0_calibscale_calibration,
+		       S_IWUSR, NULL, ad7746_start_gain_calib, CIN1);
+static IIO_DEVICE_ATTR(in_capacitance1_calibscale_calibration,
+		       S_IWUSR, NULL, ad7746_start_gain_calib, CIN2);
+static IIO_DEVICE_ATTR(in_voltage0_calibscale_calibration,
+		       S_IWUSR, NULL, ad7746_start_gain_calib, VIN);
+
+static ssize_t ad7746_show_cap_filter_rate_setup(struct device *dev,
+		struct device_attribute *attr,
+		char *buf)
+{
+	struct iio_dev *indio_dev = dev_get_drvdata(dev);
+	struct ad7746_chip_info *chip = iio_priv(indio_dev);
+
+	return sprintf(buf, "%d\n", ad7746_cap_filter_rate_table[
+			(chip->config >> 3) & 0x7][0]);
+}
+
+static ssize_t ad7746_store_cap_filter_rate_setup(struct device *dev,
+		struct device_attribute *attr,
+		const char *buf,
+		size_t len)
+{
+	struct iio_dev *indio_dev = dev_get_drvdata(dev);
+	struct ad7746_chip_info *chip = iio_priv(indio_dev);
+	u8 data;
+	int ret, i;
+
+	ret = kstrtou8(buf, 10, &data);
+	if (ret < 0)
+		return ret;
+
+	for (i = 0; i < ARRAY_SIZE(ad7746_cap_filter_rate_table); i++)
+		if (data >= ad7746_cap_filter_rate_table[i][0])
+			break;
+
+	if (i >= ARRAY_SIZE(ad7746_cap_filter_rate_table))
+		i = ARRAY_SIZE(ad7746_cap_filter_rate_table) - 1;
+
+	mutex_lock(&indio_dev->mlock);
+	chip->config &= ~AD7746_CONF_CAPFS(0x7);
+	chip->config |= AD7746_CONF_CAPFS(i);
+	mutex_unlock(&indio_dev->mlock);
+
+	return len;
+}
+
+static ssize_t ad7746_show_vt_filter_rate_setup(struct device *dev,
+		struct device_attribute *attr,
+		char *buf)
+{
+	struct iio_dev *indio_dev = dev_get_drvdata(dev);
+	struct ad7746_chip_info *chip = iio_priv(indio_dev);
+
+	return sprintf(buf, "%d\n", ad7746_vt_filter_rate_table[
+			(chip->config >> 6) & 0x3][0]);
+}
+
+static ssize_t ad7746_store_vt_filter_rate_setup(struct device *dev,
+		struct device_attribute *attr,
+		const char *buf,
+		size_t len)
+{
+	struct iio_dev *indio_dev = dev_get_drvdata(dev);
+	struct ad7746_chip_info *chip = iio_priv(indio_dev);
+	u8 data;
+	int ret, i;
+
+	ret = kstrtou8(buf, 10, &data);
+	if (ret < 0)
+		return ret;
+
+	for (i = 0; i < ARRAY_SIZE(ad7746_vt_filter_rate_table); i++)
+		if (data >= ad7746_vt_filter_rate_table[i][0])
+			break;
+
+	if (i >= ARRAY_SIZE(ad7746_vt_filter_rate_table))
+		i = ARRAY_SIZE(ad7746_vt_filter_rate_table) - 1;
+
+	mutex_lock(&indio_dev->mlock);
+	chip->config &= ~AD7746_CONF_VTFS(0x3);
+	chip->config |= AD7746_CONF_VTFS(i);
+	mutex_unlock(&indio_dev->mlock);
+
+	return len;
+}
+
+static IIO_DEVICE_ATTR(in_capacitance_sampling_frequency,
+		       S_IRUGO | S_IWUSR, ad7746_show_cap_filter_rate_setup,
+			ad7746_store_cap_filter_rate_setup, 0);
+
+static IIO_DEVICE_ATTR(in_voltage_sampling_frequency,
+		       S_IRUGO | S_IWUSR, ad7746_show_vt_filter_rate_setup,
+		       ad7746_store_vt_filter_rate_setup, 0);
+
+static IIO_CONST_ATTR(in_voltage_sampling_frequency_available, "50 31 16 8");
+static IIO_CONST_ATTR(in_capacitance_sampling_frequency_available,
+		       "91 84 50 26 16 13 11 9");
+
+static struct attribute *ad7746_attributes[] = {
+	&iio_dev_attr_in_capacitance_sampling_frequency.dev_attr.attr,
+	&iio_dev_attr_in_voltage_sampling_frequency.dev_attr.attr,
+	&iio_dev_attr_in_capacitance0_calibbias_calibration.dev_attr.attr,
+	&iio_dev_attr_in_capacitance0_calibscale_calibration.dev_attr.attr,
+	&iio_dev_attr_in_capacitance1_calibscale_calibration.dev_attr.attr,
+	&iio_dev_attr_in_capacitance1_calibbias_calibration.dev_attr.attr,
+	&iio_dev_attr_in_voltage0_calibscale_calibration.dev_attr.attr,
+	&iio_const_attr_in_voltage_sampling_frequency_available.dev_attr.attr,
+	&iio_const_attr_in_capacitance_sampling_frequency_available.
+	dev_attr.attr,
+	NULL,
+};
+
+static const struct attribute_group ad7746_attribute_group = {
+	.attrs = ad7746_attributes,
+};
+
+static int ad7746_write_raw(struct iio_dev *indio_dev,
+			    struct iio_chan_spec const *chan,
+			    int val,
+			    int val2,
+			    long mask)
+{
+	struct ad7746_chip_info *chip = iio_priv(indio_dev);
+	int ret, reg;
+
+	mutex_lock(&indio_dev->mlock);
+
+	switch (mask) {
+	case (1 << IIO_CHAN_INFO_CALIBSCALE_SEPARATE):
+		if (val != 1) {
+			ret = -EINVAL;
+			goto out;
+		}
+
+		val = (val2 * 1024) / 15625;
+
+		switch (chan->type) {
+		case IIO_CAPACITANCE:
+			reg = AD7746_REG_CAP_GAINH;
+			break;
+		case IIO_VOLTAGE:
+			reg = AD7746_REG_VOLT_GAINH;
+			break;
+		default:
+			ret = -EINVAL;
+			goto out;
+		}
+
+		ret = i2c_smbus_write_word_data(chip->client, reg, swab16(val));
+		if (ret < 0)
+			goto out;
+
+		ret = 0;
+		break;
+	case (1 << IIO_CHAN_INFO_CALIBBIAS_SHARED):
+		if ((val < 0) | (val > 0xFFFF)) {
+			ret = -EINVAL;
+			goto out;
+		}
+		ret = i2c_smbus_write_word_data(chip->client,
+				AD7746_REG_CAP_OFFH, swab16(val));
+		if (ret < 0)
+			goto out;
+
+		ret = 0;
+		break;
+	case (1 << IIO_CHAN_INFO_OFFSET_SEPARATE):
+		if ((val < 0) | (val > 43008000)) { /* 21pF */
+			ret = -EINVAL;
+			goto out;
+		}
+
+		/* CAPDAC Scale = 21pF_typ / 127
+		 * CIN Scale = 8.192pF / 2^24
+		 * Offset Scale = CAPDAC Scale / CIN Scale = 338646
+		 * */
+
+		val /= 338646;
+
+		chip->capdac[chan->channel][chan->differential] = (val > 0 ?
+			AD7746_CAPDAC_DACP(val) | AD7746_CAPDAC_DACEN : 0);
+
+		ret = i2c_smbus_write_byte_data(chip->client,
+			AD7746_REG_CAPDACA,
+			chip->capdac[chan->channel][0]);
+		if (ret < 0)
+			goto out;
+		ret = i2c_smbus_write_byte_data(chip->client,
+			AD7746_REG_CAPDACB,
+			chip->capdac[chan->channel][1]);
+		if (ret < 0)
+			goto out;
+
+		chip->capdac_set = chan->channel;
+
+		ret = 0;
+		break;
+	default:
+		ret = -EINVAL;
+	}
+
+out:
+	mutex_unlock(&indio_dev->mlock);
+	return ret;
+}
+static int ad7746_read_raw(struct iio_dev *indio_dev,
+			   struct iio_chan_spec const *chan,
+			   int *val, int *val2,
+			   long mask)
+{
+	struct ad7746_chip_info *chip = iio_priv(indio_dev);
+	int ret, delay;
+	u8 regval, reg;
+
+	union {
+		u32 d32;
+		u8 d8[4];
+	} data;
+
+	mutex_lock(&indio_dev->mlock);
+
+	switch (mask) {
+	case 0:
+		ret = ad7746_select_channel(indio_dev, chan);
+		if (ret < 0)
+			goto out;
+		delay = ret;
+
+		regval = chip->config | AD7746_CONF_MODE_SINGLE_CONV;
+		ret = i2c_smbus_write_byte_data(chip->client, AD7746_REG_CFG,
+				regval);
+		if (ret < 0)
+			goto out;
+
+		msleep(delay);
+		/* Now read the actual register */
+
+		ret = i2c_smbus_read_i2c_block_data(chip->client,
+			chan->address >> 8, 3, &data.d8[1]);
+
+		if (ret < 0)
+			goto out;
+
+		*val = (be32_to_cpu(data.d32) & 0xFFFFFF) - 0x800000;
+
+		switch (chan->type) {
+		case IIO_TEMP:
+		/* temperature in milli degrees Celsius
+		 * T = ((*val / 2048) - 4096) * 1000
+		 */
+			*val = (*val * 125) / 256;
+			break;
+		case IIO_VOLTAGE:
+			if (chan->channel == 1) /* supply_raw*/
+				*val = *val * 6;
+				break;
+		default:
+			break;
+		}
+
+		ret = IIO_VAL_INT;
+		break;
+	case (1 << IIO_CHAN_INFO_CALIBSCALE_SEPARATE):
+		switch (chan->type) {
+		case IIO_CAPACITANCE:
+			reg = AD7746_REG_CAP_GAINH;
+			break;
+		case IIO_VOLTAGE:
+			reg = AD7746_REG_VOLT_GAINH;
+			break;
+		default:
+			ret = -EINVAL;
+			goto out;
+		}
+
+		ret = i2c_smbus_read_word_data(chip->client, reg);
+		if (ret < 0)
+			goto out;
+		/* 1 + gain_val / 2^16 */
+		*val = 1;
+		*val2 = (15625 * swab16(ret)) / 1024;
+
+		ret = IIO_VAL_INT_PLUS_MICRO;
+		break;
+	case (1 << IIO_CHAN_INFO_CALIBBIAS_SHARED):
+		ret = i2c_smbus_read_word_data(chip->client,
+					       AD7746_REG_CAP_OFFH);
+		if (ret < 0)
+			goto out;
+		*val = swab16(ret);
+
+		ret = IIO_VAL_INT;
+		break;
+	case (1 << IIO_CHAN_INFO_OFFSET_SEPARATE):
+		*val = AD7746_CAPDAC_DACP(chip->capdac[chan->channel]
+			[chan->differential]) * 338646;
+
+		ret = IIO_VAL_INT;
+		break;
+	case (1 << IIO_CHAN_INFO_SCALE_SHARED):
+		switch (chan->type) {
+		case IIO_CAPACITANCE:
+			/* 8.192pf / 2^24 */
+			*val2 = 488;
+			*val =  0;
+			break;
+		case IIO_VOLTAGE:
+			/* 1170mV / 2^23 */
+			*val2 = 139475;
+			*val =  0;
+			break;
+		default:
+			ret =  -EINVAL;
+			goto out;
+		}
+
+		ret = IIO_VAL_INT_PLUS_NANO;
+		break;
+	default:
+		ret = -EINVAL;
+	};
+out:
+	mutex_unlock(&indio_dev->mlock);
+	return ret;
+}
+
+static const struct iio_info ad7746_info = {
+	.attrs = &ad7746_attribute_group,
+	.read_raw = &ad7746_read_raw,
+	.write_raw = &ad7746_write_raw,
+	.driver_module = THIS_MODULE,
+};
+
+/*
+ * device probe and remove
+ */
+
+static int __devinit ad7746_probe(struct i2c_client *client,
+		const struct i2c_device_id *id)
+{
+	struct ad7746_platform_data *pdata = client->dev.platform_data;
+	struct ad7746_chip_info *chip;
+	struct iio_dev *indio_dev;
+	int ret = 0;
+	unsigned char regval = 0;
+
+	indio_dev = iio_allocate_device(sizeof(*chip));
+	if (indio_dev == NULL) {
+		ret = -ENOMEM;
+		goto error_ret;
+	}
+	chip = iio_priv(indio_dev);
+	/* this is only used for device removal purposes */
+	i2c_set_clientdata(client, indio_dev);
+
+	chip->client = client;
+	chip->capdac_set = -1;
+
+	/* Establish that the iio_dev is a child of the i2c device */
+	indio_dev->name = id->name;
+	indio_dev->dev.parent = &client->dev;
+	indio_dev->info = &ad7746_info;
+	indio_dev->channels = ad7746_channels;
+	if (id->driver_data == 7746)
+		indio_dev->num_channels = ARRAY_SIZE(ad7746_channels);
+	else
+		indio_dev->num_channels =  ARRAY_SIZE(ad7746_channels) - 2;
+	indio_dev->num_channels = ARRAY_SIZE(ad7746_channels);
+	indio_dev->modes = INDIO_DIRECT_MODE;
+
+	if (pdata) {
+		if (pdata->exca_en) {
+			if (pdata->exca_inv_en)
+				regval |= AD7746_EXCSETUP_NEXCA;
+			else
+				regval |= AD7746_EXCSETUP_EXCA;
+		}
+
+		if (pdata->excb_en) {
+			if (pdata->excb_inv_en)
+				regval |= AD7746_EXCSETUP_NEXCB;
+			else
+				regval |= AD7746_EXCSETUP_EXCB;
+		}
+
+		regval |= AD7746_EXCSETUP_EXCLVL(pdata->exclvl);
+	} else {
+		dev_warn(&client->dev, "No platform data? using default\n");
+		regval = AD7746_EXCSETUP_EXCA | AD7746_EXCSETUP_EXCB |
+			AD7746_EXCSETUP_EXCLVL(3);
+	}
+
+	ret = i2c_smbus_write_byte_data(chip->client,
+					AD7746_REG_EXC_SETUP, regval);
+	if (ret < 0)
+		goto error_free_dev;
+
+	ret = iio_device_register(indio_dev);
+	if (ret)
+		goto error_free_dev;
+
+	dev_info(&client->dev, "%s capacitive sensor registered\n", id->name);
+
+	return 0;
+
+error_free_dev:
+	iio_free_device(indio_dev);
+error_ret:
+	return ret;
+}
+
+static int __devexit ad7746_remove(struct i2c_client *client)
+{
+	struct iio_dev *indio_dev = i2c_get_clientdata(client);
+
+	iio_device_unregister(indio_dev);
+
+	return 0;
+}
+
+static const struct i2c_device_id ad7746_id[] = {
+	{ "ad7745", 7745 },
+	{ "ad7746", 7746 },
+	{ "ad7747", 7747 },
+	{}
+};
+
+MODULE_DEVICE_TABLE(i2c, ad7746_id);
+
+static struct i2c_driver ad7746_driver = {
+	.driver = {
+		.name = KBUILD_MODNAME,
+	},
+	.probe = ad7746_probe,
+	.remove = __devexit_p(ad7746_remove),
+	.id_table = ad7746_id,
+};
+
+static __init int ad7746_init(void)
+{
+	return i2c_add_driver(&ad7746_driver);
+}
+
+static __exit void ad7746_exit(void)
+{
+	i2c_del_driver(&ad7746_driver);
+}
+
+MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
+MODULE_DESCRIPTION("Analog Devices AD7746/5/7 capacitive sensor driver");
+MODULE_LICENSE("GPL v2");
+
+module_init(ad7746_init);
+module_exit(ad7746_exit);
diff --git a/drivers/staging/iio/adc/ad7746.h b/drivers/staging/iio/adc/ad7746.h
new file mode 100644
index 0000000..ea8572d
--- /dev/null
+++ b/drivers/staging/iio/adc/ad7746.h
@@ -0,0 +1,29 @@
+/*
+ * AD7746 capacitive sensor driver supporting AD7745, AD7746 and AD7747
+ *
+ * Copyright 2011 Analog Devices Inc.
+ *
+ * Licensed under the GPL-2.
+ */
+
+#ifndef IIO_CDC_AD7746_H_
+#define IIO_CDC_AD7746_H_
+
+/*
+ * TODO: struct ad7746_platform_data needs to go into include/linux/iio
+ */
+
+#define AD7466_EXCLVL_0		0 /* +-VDD/8 */
+#define AD7466_EXCLVL_1		1 /* +-VDD/4 */
+#define AD7466_EXCLVL_2		2 /* +-VDD * 3/8 */
+#define AD7466_EXCLVL_3		3 /* +-VDD/2 */
+
+struct ad7746_platform_data {
+	unsigned char exclvl;	/*Excitation Voltage Level */
+	bool exca_en;		/* enables EXCA pin as the excitation output */
+	bool exca_inv_en;	/* enables /EXCA pin as the excitation output */
+	bool excb_en;		/* enables EXCB pin as the excitation output */
+	bool excb_inv_en;	/* enables /EXCB pin as the excitation output */
+};
+
+#endif /* IIO_CDC_AD7746_H_ */
-- 
1.7.0.4

^ permalink raw reply related	[flat|nested] 6+ messages in thread

* Re: [PATCH] iio: adc: Replace, rewrite ad7745 from scratch.
  2011-09-16 14:47 michael.hennerich
@ 2011-09-19 12:19 ` Jonathan Cameron
  2011-09-19 12:54   ` Jonathan Cameron
  2011-09-19 19:44   ` Hennerich, Michael
  0 siblings, 2 replies; 6+ messages in thread
From: Jonathan Cameron @ 2011-09-19 12:19 UTC (permalink / raw)
  To: michael.hennerich; +Cc: linux-iio, device-drivers-devel, drivers


One quick nitpick on submission format:
Please put version in the email subject
[PATCH V3] iio:...

That way it's easy to spot which one to bother reading ;)

On 09/16/11 15:47, michael.hennerich@analog.com wrote:
> From: Michael Hennerich <michael.hennerich@analog.com>
> 
> The existing ad7745 driver didn't conform with the IIO spec for such devices.
> It was way simpler to rewrite the existing driver, than actually fixing it.
> 
> Changes since V1:
> 
> Fix file header description.
> Fix erroneous defines.
> Pin channels to expected places in the iio_chan_spec array, to avoid magic numbers.
> Use msleep instead of busy waiting mdelay.
> Fix indention style.
> Drop _bias and use _offset attribute.
> 
> Changes since V2:
> Increase accuracy of cap scale.
> Fix channel spec for VIN.
Some formatting nitpicks. I'll fix them up.

I don't think Greg's tree is visible anywhere so I'll pull this through mine
and push on to him.  Thanks,

> 
> Signed-off-by: Michael Hennerich <michael.hennerich@analog.com>
Signed-off-by: Jonathan Cameron <jic23@cam.ac.uk>
> ---
>  drivers/staging/iio/adc/Kconfig  |    2 +-
>  drivers/staging/iio/adc/Makefile |    2 +-
>  drivers/staging/iio/adc/ad7745.c |  672 --------------------------------
>  drivers/staging/iio/adc/ad7746.c |  800 ++++++++++++++++++++++++++++++++++++++
>  drivers/staging/iio/adc/ad7746.h |   29 ++
>  5 files changed, 831 insertions(+), 674 deletions(-)
>  delete mode 100644 drivers/staging/iio/adc/ad7745.c
>  create mode 100644 drivers/staging/iio/adc/ad7746.c
>  create mode 100644 drivers/staging/iio/adc/ad7746.h
> 
> diff --git a/drivers/staging/iio/adc/Kconfig b/drivers/staging/iio/adc/Kconfig
> index 7867ab1..0482073 100644
> --- a/drivers/staging/iio/adc/Kconfig
> +++ b/drivers/staging/iio/adc/Kconfig
> @@ -144,7 +144,7 @@ config AD7793
>  	  To compile this driver as a module, choose M here: the
>  	  module will be called AD7793.
>  
> -config AD7745
> +config AD7746
>  	tristate "Analog Devices AD7745, AD7746 AD7747 capacitive sensor driver"
>  	depends on I2C
>  	help
... snip old driver out as we don't care ;)....
> diff --git a/drivers/staging/iio/adc/ad7746.c b/drivers/staging/iio/adc/ad7746.c
> new file mode 100644
> index 0000000..b2011f5
> --- /dev/null
> +++ b/drivers/staging/iio/adc/ad7746.c
> @@ -0,0 +1,800 @@
> +/*
> + * AD7746 capacitive sensor driver supporting AD7745, AD7746 and AD7747
> + *
> + * Copyright 2011 Analog Devices Inc.
> + *
> + * Licensed under the GPL-2.
> + */
> +
> +#include <linux/interrupt.h>
> +#include <linux/device.h>
> +#include <linux/kernel.h>
> +#include <linux/slab.h>
> +#include <linux/sysfs.h>
> +#include <linux/i2c.h>
> +#include <linux/delay.h>
> +
> +#include "../iio.h"
> +#include "../sysfs.h"
> +
> +#include "ad7746.h"
> +
> +/*
> + * AD7746 Register Definition
> + */
> +
> +#define AD7746_REG_STATUS		0
> +#define AD7746_REG_CAP_DATA_HIGH	1
> +#define AD7746_REG_CAP_DATA_MID		2
> +#define AD7746_REG_CAP_DATA_LOW		3
> +#define AD7746_REG_VT_DATA_HIGH		4
> +#define AD7746_REG_VT_DATA_MID		5
> +#define AD7746_REG_VT_DATA_LOW		6
> +#define AD7746_REG_CAP_SETUP		7
> +#define AD7746_REG_VT_SETUP		8
> +#define AD7746_REG_EXC_SETUP		9
> +#define AD7746_REG_CFG			10
> +#define AD7746_REG_CAPDACA		11
> +#define AD7746_REG_CAPDACB		12
> +#define AD7746_REG_CAP_OFFH		13
> +#define AD7746_REG_CAP_OFFL		14
> +#define AD7746_REG_CAP_GAINH		15
> +#define AD7746_REG_CAP_GAINL		16
> +#define AD7746_REG_VOLT_GAINH		17
> +#define AD7746_REG_VOLT_GAINL		18
> +
> +/* Status Register Bit Designations (AD7746_REG_STATUS) */
> +#define AD7746_STATUS_EXCERR		(1 << 3)
> +#define AD7746_STATUS_RDY		(1 << 2)
> +#define AD7746_STATUS_RDYVT		(1 << 1)
> +#define AD7746_STATUS_RDYCAP		(1 << 0)
> +
> +/* Capacitive Channel Setup Register Bit Designations (AD7746_REG_CAP_SETUP) */
> +#define AD7746_CAPSETUP_CAPEN		(1 << 7)
> +#define AD7746_CAPSETUP_CIN2		(1 << 6) /* AD7746 only */
> +#define AD7746_CAPSETUP_CAPDIFF		(1 << 5)
> +#define AD7746_CAPSETUP_CACHOP		(1 << 0)
> +
> +/* Voltage/Temperature Setup Register Bit Designations (AD7746_REG_VT_SETUP) */
> +#define AD7746_VTSETUP_VTEN		(1 << 7)
> +#define AD7746_VTSETUP_VTMD_INT_TEMP	(0 << 5)
> +#define AD7746_VTSETUP_VTMD_EXT_TEMP	(1 << 5)
> +#define AD7746_VTSETUP_VTMD_VDD_MON	(2 << 5)
> +#define AD7746_VTSETUP_VTMD_EXT_VIN	(3 << 5)
> +#define AD7746_VTSETUP_EXTREF		(1 << 4)
> +#define AD7746_VTSETUP_VTSHORT		(1 << 1)
> +#define AD7746_VTSETUP_VTCHOP		(1 << 0)
> +
> +/* Excitation Setup Register Bit Designations (AD7746_REG_EXC_SETUP) */
> +#define AD7746_EXCSETUP_CLKCTRL		(1 << 7)
> +#define AD7746_EXCSETUP_EXCON		(1 << 6)
> +#define AD7746_EXCSETUP_EXCB		(1 << 5)
> +#define AD7746_EXCSETUP_NEXCB		(1 << 4)
> +#define AD7746_EXCSETUP_EXCA		(1 << 3)
> +#define AD7746_EXCSETUP_NEXCA		(1 << 2)
> +#define AD7746_EXCSETUP_EXCLVL(x)	(((x) & 0x3) << 0)
> +
> +/* Config Register Bit Designations (AD7746_REG_CFG) */
> +#define AD7746_CONF_VTFS(x)		((x) << 6)
> +#define AD7746_CONF_CAPFS(x)		((x) << 3)
> +#define AD7746_CONF_MODE_IDLE		(0 << 0)
> +#define AD7746_CONF_MODE_CONT_CONV	(1 << 0)
> +#define AD7746_CONF_MODE_SINGLE_CONV	(2 << 0)
> +#define AD7746_CONF_MODE_PWRDN		(3 << 0)
> +#define AD7746_CONF_MODE_OFFS_CAL	(5 << 0)
> +#define AD7746_CONF_MODE_GAIN_CAL	(6 << 0)
> +
> +/* CAPDAC Register Bit Designations (AD7746_REG_CAPDACx) */
> +#define AD7746_CAPDAC_DACEN		(1 << 7)
> +#define AD7746_CAPDAC_DACP(x)		((x) & 0x7F)
> +
> +/*
> + * struct ad7746_chip_info - chip specifc information
> + */
> +
> +struct ad7746_chip_info {
> +	struct i2c_client *client;
> +	/*
> +	 * Capacitive channel digital filter setup;
> +	 * conversion time/update rate setup per channel
> +	 */
> +	u8	config;
> +	u8	cap_setup;
> +	u8	vt_setup;
> +	u8	capdac[2][2];
> +	s8	capdac_set;
> +};
> +
> +enum ad7746_chan {
> +	VIN,
> +	VIN_VDD,
> +	TEMP_INT,
> +	TEMP_EXT,
> +	CIN1,
> +	CIN1_DIFF,
> +	CIN2,
> +	CIN2_DIFF,
> +};
> +
> +static const struct iio_chan_spec ad7746_channels[] = {
> +	[VIN] = {
> +		.type = IIO_VOLTAGE,
> +		.indexed = 1,
> +		.channel = 0,
> +		.info_mask = (1 << IIO_CHAN_INFO_SCALE_SHARED),
> +		.address = AD7746_REG_VT_DATA_HIGH << 8 |
> +			AD7746_VTSETUP_VTMD_EXT_VIN,
> +	},
> +	[VIN_VDD] = {
> +		.type = IIO_VOLTAGE,
> +		.indexed = 1,
> +		.channel = 1,
> +		.extend_name = "supply",
> +		.info_mask = (1 << IIO_CHAN_INFO_SCALE_SHARED),
> +		.address = AD7746_REG_VT_DATA_HIGH << 8 |
> +			AD7746_VTSETUP_VTMD_VDD_MON,
> +	},
> +	[TEMP_INT] = {
> +		.type = IIO_TEMP,
> +		.indexed = 1,
> +		.channel = 0,
> +		.processed_val = IIO_PROCESSED,
> +		.address = AD7746_REG_VT_DATA_HIGH << 8 |
> +			AD7746_VTSETUP_VTMD_INT_TEMP,
> +	},
> +	[TEMP_EXT] = {
> +		.type = IIO_TEMP,
> +		.indexed = 1,
> +		.channel = 1,
> +		.processed_val = IIO_PROCESSED,
> +		.address = AD7746_REG_VT_DATA_HIGH << 8 |
> +			AD7746_VTSETUP_VTMD_EXT_TEMP,
> +	},
> +	[CIN1] = {
> +		.type = IIO_CAPACITANCE,
> +		.indexed = 1,
> +		.channel = 0,
> +		.info_mask = (1 << IIO_CHAN_INFO_CALIBSCALE_SEPARATE) |
> +		(1 << IIO_CHAN_INFO_CALIBBIAS_SHARED) |
> +		(1 << IIO_CHAN_INFO_OFFSET_SEPARATE) |
> +		(1 << IIO_CHAN_INFO_SCALE_SHARED),
> +		.address = AD7746_REG_CAP_DATA_HIGH << 8,
> +	},
> +	[CIN1_DIFF] = {
> +		.type = IIO_CAPACITANCE,
> +		.differential = 1,
> +		.indexed = 1,
> +		.channel = 0,
> +		.channel2 = 2,
> +		.info_mask = (1 << IIO_CHAN_INFO_CALIBSCALE_SEPARATE) |
> +		(1 << IIO_CHAN_INFO_CALIBBIAS_SHARED) |
> +		(1 << IIO_CHAN_INFO_OFFSET_SEPARATE) |
> +		(1 << IIO_CHAN_INFO_SCALE_SHARED),
> +		.address = AD7746_REG_CAP_DATA_HIGH << 8 |
> +			AD7746_CAPSETUP_CAPDIFF
> +	},
> +	[CIN2] = {
> +		.type = IIO_CAPACITANCE,
> +		.indexed = 1,
> +		.channel = 1,
> +		.info_mask = (1 << IIO_CHAN_INFO_CALIBSCALE_SEPARATE) |
> +		(1 << IIO_CHAN_INFO_CALIBBIAS_SHARED) |
> +		(1 << IIO_CHAN_INFO_OFFSET_SEPARATE) |
> +		(1 << IIO_CHAN_INFO_SCALE_SHARED),
> +		.address = AD7746_REG_CAP_DATA_HIGH << 8 |
> +			AD7746_CAPSETUP_CIN2,
> +	},
> +	[CIN2_DIFF] = {
> +		.type = IIO_CAPACITANCE,
> +		.differential = 1,
> +		.indexed = 1,
> +		.channel = 1,
> +		.channel2 = 3,
> +		.info_mask = (1 << IIO_CHAN_INFO_CALIBSCALE_SEPARATE) |
> +		(1 << IIO_CHAN_INFO_CALIBBIAS_SHARED) |
> +		(1 << IIO_CHAN_INFO_OFFSET_SEPARATE) |
> +		(1 << IIO_CHAN_INFO_SCALE_SHARED),
> +		.address = AD7746_REG_CAP_DATA_HIGH << 8 |
> +			AD7746_CAPSETUP_CAPDIFF | AD7746_CAPSETUP_CIN2,
> +	}
> +};
> +
> +/* Values are Update Rate (Hz), Conversion Time (ms) + 1*/
> +static const unsigned char ad7746_vt_filter_rate_table[][2] = {
> +	{50, 20 + 1}, {31, 32 + 1}, {16, 62 + 1}, {8, 122 + 1},
> +};
> +
> +static const unsigned char ad7746_cap_filter_rate_table[][2] = {
> +	{91, 11 + 1}, {84, 12 + 1}, {50, 20 + 1}, {26, 38 + 1},
> +	{16, 62 + 1}, {13, 77 + 1}, {11, 92 + 1}, {9, 110 + 1},
> +};
> +
> +static int ad7746_select_channel(struct iio_dev *indio_dev,
> +			    struct iio_chan_spec const *chan)
> +{
> +	struct ad7746_chip_info *chip = iio_priv(indio_dev);
> +	int ret, delay;
> +	u8 vt_setup, cap_setup;
> +
> +	switch (chan->type) {
> +	case IIO_CAPACITANCE:
> +		cap_setup = (chan->address & 0xFF) | AD7746_CAPSETUP_CAPEN;
> +		vt_setup = chip->vt_setup & ~AD7746_VTSETUP_VTEN;
> +		delay = ad7746_cap_filter_rate_table[(chip->config >> 3) &
> +			0x7][1];
> +
> +		if (chip->capdac_set != chan->channel) {
> +			ret = i2c_smbus_write_byte_data(chip->client,
> +				AD7746_REG_CAPDACA,
> +				chip->capdac[chan->channel][0]);
> +			if (ret < 0)
> +				return ret;
> +			ret = i2c_smbus_write_byte_data(chip->client,
> +				AD7746_REG_CAPDACB,
> +				chip->capdac[chan->channel][1]);
> +			if (ret < 0)
> +				return ret;
> +
> +			chip->capdac_set = chan->channel;
> +		}
> +		break;
> +	case IIO_VOLTAGE:
> +	case IIO_TEMP:
> +		vt_setup = (chan->address & 0xFF) | AD7746_VTSETUP_VTEN;
> +		cap_setup = chip->cap_setup & ~AD7746_CAPSETUP_CAPEN;
> +		delay = ad7746_cap_filter_rate_table[(chip->config >> 6) &
> +			0x3][1];
> +		break;
> +	default:
> +		return -EINVAL;
> +	}
> +
> +	if (chip->cap_setup != cap_setup) {
> +		ret = i2c_smbus_write_byte_data(chip->client,
> +						AD7746_REG_CAP_SETUP,
> +						cap_setup);
> +		if (ret < 0)
> +			return ret;
> +
> +		chip->cap_setup = cap_setup;
> +	}
> +
> +	if (chip->vt_setup != vt_setup) {
> +		ret = i2c_smbus_write_byte_data(chip->client,
> +						AD7746_REG_VT_SETUP,
> +						vt_setup);
> +		if (ret < 0)
> +			return ret;
> +
> +		chip->vt_setup = vt_setup;
> +	}
> +
> +	return delay;
> +}
> +
> +static inline ssize_t ad7746_start_calib(struct device *dev,
> +					 struct device_attribute *attr,
> +					 const char *buf,
> +					 size_t len,
> +					 u8 regval)
> +{
> +	struct iio_dev *indio_dev = dev_get_drvdata(dev);
> +	struct ad7746_chip_info *chip = iio_priv(indio_dev);
> +	bool doit;
> +	int ret, timeout = 10;
> +
> +	ret = strtobool(buf, &doit);
> +	if (ret < 0)
> +		return ret;
> +
> +	if (!doit)
> +		return 0;
> +
> +	mutex_lock(&indio_dev->mlock);
> +	regval |= chip->config;
> +	ret = i2c_smbus_write_byte_data(chip->client, AD7746_REG_CFG, regval);
> +	if (ret < 0) {
> +		mutex_unlock(&indio_dev->mlock);
> +		return ret;
> +	}
> +
> +	do {
> +		msleep(20);
> +		ret = i2c_smbus_read_byte_data(chip->client, AD7746_REG_CFG);
> +		if (ret < 0) {
> +			mutex_unlock(&indio_dev->mlock);
> +			return ret;
> +		}
> +	} while ((ret == regval) && timeout--);
> +
> +	mutex_unlock(&indio_dev->mlock);
> +	return len;
> +}
Blank line here please.
> +static ssize_t ad7746_start_offset_calib(struct device *dev,
> +					 struct device_attribute *attr,
> +					 const char *buf,
> +					 size_t len)
> +{
> +	struct iio_dev *indio_dev = dev_get_drvdata(dev);
> +	int ret = ad7746_select_channel(indio_dev,
> +			      &ad7746_channels[to_iio_dev_attr(attr)->address]);
> +	if (ret < 0)
> +		return ret;
> +
> +	return ad7746_start_calib(dev, attr, buf, len,
> +				  AD7746_CONF_MODE_OFFS_CAL);
> +}
Blank line.
> +static ssize_t ad7746_start_gain_calib(struct device *dev,
> +				       struct device_attribute *attr,
> +				       const char *buf,
> +				       size_t len)
> +{
> +	struct iio_dev *indio_dev = dev_get_drvdata(dev);
> +	int ret = ad7746_select_channel(indio_dev,
> +			      &ad7746_channels[to_iio_dev_attr(attr)->address]);
> +	if (ret < 0)
> +		return ret;
> +
> +	return ad7746_start_calib(dev, attr, buf, len,
> +				  AD7746_CONF_MODE_GAIN_CAL);
> +}
> +
> +static IIO_DEVICE_ATTR(in_capacitance0_calibbias_calibration,
> +		       S_IWUSR, NULL, ad7746_start_offset_calib, CIN1);
> +static IIO_DEVICE_ATTR(in_capacitance1_calibbias_calibration,
> +		       S_IWUSR, NULL, ad7746_start_offset_calib, CIN2);
> +static IIO_DEVICE_ATTR(in_capacitance0_calibscale_calibration,
> +		       S_IWUSR, NULL, ad7746_start_gain_calib, CIN1);
> +static IIO_DEVICE_ATTR(in_capacitance1_calibscale_calibration,
> +		       S_IWUSR, NULL, ad7746_start_gain_calib, CIN2);
> +static IIO_DEVICE_ATTR(in_voltage0_calibscale_calibration,
> +		       S_IWUSR, NULL, ad7746_start_gain_calib, VIN);
> +
> +static ssize_t ad7746_show_cap_filter_rate_setup(struct device *dev,
> +		struct device_attribute *attr,
> +		char *buf)
> +{
> +	struct iio_dev *indio_dev = dev_get_drvdata(dev);
> +	struct ad7746_chip_info *chip = iio_priv(indio_dev);
> +
> +	return sprintf(buf, "%d\n", ad7746_cap_filter_rate_table[
> +			(chip->config >> 3) & 0x7][0]);
> +}
> +
> +static ssize_t ad7746_store_cap_filter_rate_setup(struct device *dev,
> +		struct device_attribute *attr,
> +		const char *buf,
> +		size_t len)
> +{
> +	struct iio_dev *indio_dev = dev_get_drvdata(dev);
> +	struct ad7746_chip_info *chip = iio_priv(indio_dev);
> +	u8 data;
> +	int ret, i;
> +
> +	ret = kstrtou8(buf, 10, &data);
> +	if (ret < 0)
> +		return ret;
> +
> +	for (i = 0; i < ARRAY_SIZE(ad7746_cap_filter_rate_table); i++)
> +		if (data >= ad7746_cap_filter_rate_table[i][0])
> +			break;
> +
> +	if (i >= ARRAY_SIZE(ad7746_cap_filter_rate_table))
> +		i = ARRAY_SIZE(ad7746_cap_filter_rate_table) - 1;
> +
> +	mutex_lock(&indio_dev->mlock);
> +	chip->config &= ~AD7746_CONF_CAPFS(0x7);
> +	chip->config |= AD7746_CONF_CAPFS(i);
> +	mutex_unlock(&indio_dev->mlock);
> +
> +	return len;
> +}
> +
> +static ssize_t ad7746_show_vt_filter_rate_setup(struct device *dev,
> +		struct device_attribute *attr,
> +		char *buf)
> +{
> +	struct iio_dev *indio_dev = dev_get_drvdata(dev);
> +	struct ad7746_chip_info *chip = iio_priv(indio_dev);
> +
> +	return sprintf(buf, "%d\n", ad7746_vt_filter_rate_table[
> +			(chip->config >> 6) & 0x3][0]);
> +}
> +
> +static ssize_t ad7746_store_vt_filter_rate_setup(struct device *dev,
> +		struct device_attribute *attr,
> +		const char *buf,
> +		size_t len)
> +{
> +	struct iio_dev *indio_dev = dev_get_drvdata(dev);
> +	struct ad7746_chip_info *chip = iio_priv(indio_dev);
> +	u8 data;
> +	int ret, i;
> +
> +	ret = kstrtou8(buf, 10, &data);
> +	if (ret < 0)
> +		return ret;
> +
> +	for (i = 0; i < ARRAY_SIZE(ad7746_vt_filter_rate_table); i++)
> +		if (data >= ad7746_vt_filter_rate_table[i][0])
> +			break;
> +
> +	if (i >= ARRAY_SIZE(ad7746_vt_filter_rate_table))
> +		i = ARRAY_SIZE(ad7746_vt_filter_rate_table) - 1;
> +
> +	mutex_lock(&indio_dev->mlock);
> +	chip->config &= ~AD7746_CONF_VTFS(0x3);
> +	chip->config |= AD7746_CONF_VTFS(i);
> +	mutex_unlock(&indio_dev->mlock);
> +
> +	return len;
> +}
> +
> +static IIO_DEVICE_ATTR(in_capacitance_sampling_frequency,
> +		       S_IRUGO | S_IWUSR, ad7746_show_cap_filter_rate_setup,
> +			ad7746_store_cap_filter_rate_setup, 0);
> +
> +static IIO_DEVICE_ATTR(in_voltage_sampling_frequency,
> +		       S_IRUGO | S_IWUSR, ad7746_show_vt_filter_rate_setup,
> +		       ad7746_store_vt_filter_rate_setup, 0);
> +
> +static IIO_CONST_ATTR(in_voltage_sampling_frequency_available, "50 31 16 8");
> +static IIO_CONST_ATTR(in_capacitance_sampling_frequency_available,
> +		       "91 84 50 26 16 13 11 9");
> +
> +static struct attribute *ad7746_attributes[] = {
> +	&iio_dev_attr_in_capacitance_sampling_frequency.dev_attr.attr,
> +	&iio_dev_attr_in_voltage_sampling_frequency.dev_attr.attr,
> +	&iio_dev_attr_in_capacitance0_calibbias_calibration.dev_attr.attr,
> +	&iio_dev_attr_in_capacitance0_calibscale_calibration.dev_attr.attr,
> +	&iio_dev_attr_in_capacitance1_calibscale_calibration.dev_attr.attr,
> +	&iio_dev_attr_in_capacitance1_calibbias_calibration.dev_attr.attr,
> +	&iio_dev_attr_in_voltage0_calibscale_calibration.dev_attr.attr,
> +	&iio_const_attr_in_voltage_sampling_frequency_available.dev_attr.attr,
> +	&iio_const_attr_in_capacitance_sampling_frequency_available.
> +	dev_attr.attr,
> +	NULL,
> +};
> +
> +static const struct attribute_group ad7746_attribute_group = {
> +	.attrs = ad7746_attributes,
> +};
> +
> +static int ad7746_write_raw(struct iio_dev *indio_dev,
> +			    struct iio_chan_spec const *chan,
> +			    int val,
> +			    int val2,
> +			    long mask)
> +{
> +	struct ad7746_chip_info *chip = iio_priv(indio_dev);
> +	int ret, reg;
> +
> +	mutex_lock(&indio_dev->mlock);
> +
> +	switch (mask) {
> +	case (1 << IIO_CHAN_INFO_CALIBSCALE_SEPARATE):
> +		if (val != 1) {
> +			ret = -EINVAL;
> +			goto out;
> +		}
> +
> +		val = (val2 * 1024) / 15625;
> +
> +		switch (chan->type) {
> +		case IIO_CAPACITANCE:
> +			reg = AD7746_REG_CAP_GAINH;
> +			break;
> +		case IIO_VOLTAGE:
> +			reg = AD7746_REG_VOLT_GAINH;
> +			break;
> +		default:
> +			ret = -EINVAL;
> +			goto out;
> +		}
> +
> +		ret = i2c_smbus_write_word_data(chip->client, reg, swab16(val));
> +		if (ret < 0)
> +			goto out;
> +
> +		ret = 0;
> +		break;
> +	case (1 << IIO_CHAN_INFO_CALIBBIAS_SHARED):
> +		if ((val < 0) | (val > 0xFFFF)) {
> +			ret = -EINVAL;
> +			goto out;
> +		}
> +		ret = i2c_smbus_write_word_data(chip->client,
> +				AD7746_REG_CAP_OFFH, swab16(val));
> +		if (ret < 0)
> +			goto out;
> +
> +		ret = 0;
> +		break;
> +	case (1 << IIO_CHAN_INFO_OFFSET_SEPARATE):
> +		if ((val < 0) | (val > 43008000)) { /* 21pF */
> +			ret = -EINVAL;
> +			goto out;
> +		}
> +
> +		/* CAPDAC Scale = 21pF_typ / 127
> +		 * CIN Scale = 8.192pF / 2^24
> +		 * Offset Scale = CAPDAC Scale / CIN Scale = 338646
> +		 * */
> +
> +		val /= 338646;
> +
> +		chip->capdac[chan->channel][chan->differential] = (val > 0 ?
> +			AD7746_CAPDAC_DACP(val) | AD7746_CAPDAC_DACEN : 0);
> +
> +		ret = i2c_smbus_write_byte_data(chip->client,
> +			AD7746_REG_CAPDACA,
> +			chip->capdac[chan->channel][0]);
> +		if (ret < 0)
> +			goto out;
> +		ret = i2c_smbus_write_byte_data(chip->client,
> +			AD7746_REG_CAPDACB,
> +			chip->capdac[chan->channel][1]);
> +		if (ret < 0)
> +			goto out;
> +
> +		chip->capdac_set = chan->channel;
> +
> +		ret = 0;
> +		break;
> +	default:
> +		ret = -EINVAL;
> +	}
> +
> +out:
> +	mutex_unlock(&indio_dev->mlock);
> +	return ret;
> +}
> +static int ad7746_read_raw(struct iio_dev *indio_dev,
> +			   struct iio_chan_spec const *chan,
> +			   int *val, int *val2,
> +			   long mask)
> +{
> +	struct ad7746_chip_info *chip = iio_priv(indio_dev);
> +	int ret, delay;
> +	u8 regval, reg;
> +
> +	union {
> +		u32 d32;
> +		u8 d8[4];
> +	} data;
> +
> +	mutex_lock(&indio_dev->mlock);
> +
> +	switch (mask) {
> +	case 0:
> +		ret = ad7746_select_channel(indio_dev, chan);
> +		if (ret < 0)
> +			goto out;
> +		delay = ret;
> +
> +		regval = chip->config | AD7746_CONF_MODE_SINGLE_CONV;
> +		ret = i2c_smbus_write_byte_data(chip->client, AD7746_REG_CFG,
> +				regval);
> +		if (ret < 0)
> +			goto out;
> +
> +		msleep(delay);
> +		/* Now read the actual register */
> +
> +		ret = i2c_smbus_read_i2c_block_data(chip->client,
> +			chan->address >> 8, 3, &data.d8[1]);
> +
> +		if (ret < 0)
> +			goto out;
> +
> +		*val = (be32_to_cpu(data.d32) & 0xFFFFFF) - 0x800000;
> +
> +		switch (chan->type) {
> +		case IIO_TEMP:
> +		/* temperature in milli degrees Celsius
> +		 * T = ((*val / 2048) - 4096) * 1000
> +		 */
> +			*val = (*val * 125) / 256;
> +			break;
> +		case IIO_VOLTAGE:
> +			if (chan->channel == 1) /* supply_raw*/
> +				*val = *val * 6;
> +				break;
> +		default:
> +			break;
> +		}
> +
> +		ret = IIO_VAL_INT;
> +		break;
> +	case (1 << IIO_CHAN_INFO_CALIBSCALE_SEPARATE):
> +		switch (chan->type) {
> +		case IIO_CAPACITANCE:
> +			reg = AD7746_REG_CAP_GAINH;
> +			break;
> +		case IIO_VOLTAGE:
> +			reg = AD7746_REG_VOLT_GAINH;
> +			break;
> +		default:
> +			ret = -EINVAL;
> +			goto out;
> +		}
> +
> +		ret = i2c_smbus_read_word_data(chip->client, reg);
> +		if (ret < 0)
> +			goto out;
> +		/* 1 + gain_val / 2^16 */
> +		*val = 1;
> +		*val2 = (15625 * swab16(ret)) / 1024;
> +
> +		ret = IIO_VAL_INT_PLUS_MICRO;
> +		break;
> +	case (1 << IIO_CHAN_INFO_CALIBBIAS_SHARED):
> +		ret = i2c_smbus_read_word_data(chip->client,
> +					       AD7746_REG_CAP_OFFH);
> +		if (ret < 0)
> +			goto out;
> +		*val = swab16(ret);
> +
> +		ret = IIO_VAL_INT;
> +		break;
> +	case (1 << IIO_CHAN_INFO_OFFSET_SEPARATE):
> +		*val = AD7746_CAPDAC_DACP(chip->capdac[chan->channel]
> +			[chan->differential]) * 338646;
> +
> +		ret = IIO_VAL_INT;
> +		break;
> +	case (1 << IIO_CHAN_INFO_SCALE_SHARED):
> +		switch (chan->type) {
> +		case IIO_CAPACITANCE:
> +			/* 8.192pf / 2^24 */
> +			*val2 = 488;
> +			*val =  0;
> +			break;
> +		case IIO_VOLTAGE:
> +			/* 1170mV / 2^23 */
> +			*val2 = 139475;
> +			*val =  0;
> +			break;
> +		default:
> +			ret =  -EINVAL;
> +			goto out;
> +		}
> +
> +		ret = IIO_VAL_INT_PLUS_NANO;
> +		break;
> +	default:
> +		ret = -EINVAL;
> +	};
> +out:
> +	mutex_unlock(&indio_dev->mlock);
> +	return ret;
> +}
> +
> +static const struct iio_info ad7746_info = {
> +	.attrs = &ad7746_attribute_group,
> +	.read_raw = &ad7746_read_raw,
> +	.write_raw = &ad7746_write_raw,
> +	.driver_module = THIS_MODULE,
> +};
> +
> +/*
> + * device probe and remove
> + */
> +
> +static int __devinit ad7746_probe(struct i2c_client *client,
> +		const struct i2c_device_id *id)
> +{
> +	struct ad7746_platform_data *pdata = client->dev.platform_data;
> +	struct ad7746_chip_info *chip;
> +	struct iio_dev *indio_dev;
> +	int ret = 0;
> +	unsigned char regval = 0;
> +
> +	indio_dev = iio_allocate_device(sizeof(*chip));
> +	if (indio_dev == NULL) {
> +		ret = -ENOMEM;
> +		goto error_ret;
> +	}
> +	chip = iio_priv(indio_dev);
> +	/* this is only used for device removal purposes */
> +	i2c_set_clientdata(client, indio_dev);
> +
> +	chip->client = client;
> +	chip->capdac_set = -1;
> +
> +	/* Establish that the iio_dev is a child of the i2c device */
> +	indio_dev->name = id->name;
> +	indio_dev->dev.parent = &client->dev;
> +	indio_dev->info = &ad7746_info;
> +	indio_dev->channels = ad7746_channels;
> +	if (id->driver_data == 7746)
> +		indio_dev->num_channels = ARRAY_SIZE(ad7746_channels);
> +	else
> +		indio_dev->num_channels =  ARRAY_SIZE(ad7746_channels) - 2;
> +	indio_dev->num_channels = ARRAY_SIZE(ad7746_channels);
> +	indio_dev->modes = INDIO_DIRECT_MODE;
> +
> +	if (pdata) {
> +		if (pdata->exca_en) {
> +			if (pdata->exca_inv_en)
> +				regval |= AD7746_EXCSETUP_NEXCA;
> +			else
> +				regval |= AD7746_EXCSETUP_EXCA;
> +		}
> +
> +		if (pdata->excb_en) {
> +			if (pdata->excb_inv_en)
> +				regval |= AD7746_EXCSETUP_NEXCB;
> +			else
> +				regval |= AD7746_EXCSETUP_EXCB;
> +		}
> +
> +		regval |= AD7746_EXCSETUP_EXCLVL(pdata->exclvl);
> +	} else {
> +		dev_warn(&client->dev, "No platform data? using default\n");
> +		regval = AD7746_EXCSETUP_EXCA | AD7746_EXCSETUP_EXCB |
> +			AD7746_EXCSETUP_EXCLVL(3);
> +	}
> +
> +	ret = i2c_smbus_write_byte_data(chip->client,
> +					AD7746_REG_EXC_SETUP, regval);
> +	if (ret < 0)
> +		goto error_free_dev;
> +
> +	ret = iio_device_register(indio_dev);
> +	if (ret)
> +		goto error_free_dev;
> +
> +	dev_info(&client->dev, "%s capacitive sensor registered\n", id->name);
> +
> +	return 0;
> +
> +error_free_dev:
> +	iio_free_device(indio_dev);
> +error_ret:
> +	return ret;
> +}
> +
> +static int __devexit ad7746_remove(struct i2c_client *client)
> +{
> +	struct iio_dev *indio_dev = i2c_get_clientdata(client);
> +
> +	iio_device_unregister(indio_dev);
> +
> +	return 0;
> +}
> +
> +static const struct i2c_device_id ad7746_id[] = {
> +	{ "ad7745", 7745 },
> +	{ "ad7746", 7746 },
> +	{ "ad7747", 7747 },
> +	{}
> +};
> +
> +MODULE_DEVICE_TABLE(i2c, ad7746_id);
> +
> +static struct i2c_driver ad7746_driver = {
> +	.driver = {
> +		.name = KBUILD_MODNAME,
> +	},
> +	.probe = ad7746_probe,
> +	.remove = __devexit_p(ad7746_remove),
> +	.id_table = ad7746_id,
> +};
> +
> +static __init int ad7746_init(void)
> +{
> +	return i2c_add_driver(&ad7746_driver);
> +}
> +
> +static __exit void ad7746_exit(void)
> +{
> +	i2c_del_driver(&ad7746_driver);
> +}
> +
> +MODULE_AUTHOR("Michael Hennerich <hennerich@blackfin.uclinux.org>");
> +MODULE_DESCRIPTION("Analog Devices AD7746/5/7 capacitive sensor driver");
> +MODULE_LICENSE("GPL v2");
> +
> +module_init(ad7746_init);
> +module_exit(ad7746_exit);
> diff --git a/drivers/staging/iio/adc/ad7746.h b/drivers/staging/iio/adc/ad7746.h
> new file mode 100644
> index 0000000..ea8572d
> --- /dev/null
> +++ b/drivers/staging/iio/adc/ad7746.h
> @@ -0,0 +1,29 @@
> +/*
> + * AD7746 capacitive sensor driver supporting AD7745, AD7746 and AD7747
> + *
> + * Copyright 2011 Analog Devices Inc.
> + *
> + * Licensed under the GPL-2.
> + */
> +
> +#ifndef IIO_CDC_AD7746_H_
> +#define IIO_CDC_AD7746_H_
> +
> +/*
> + * TODO: struct ad7746_platform_data needs to go into include/linux/iio
> + */
> +
> +#define AD7466_EXCLVL_0		0 /* +-VDD/8 */
> +#define AD7466_EXCLVL_1		1 /* +-VDD/4 */
> +#define AD7466_EXCLVL_2		2 /* +-VDD * 3/8 */
> +#define AD7466_EXCLVL_3		3 /* +-VDD/2 */
> +
> +struct ad7746_platform_data {
> +	unsigned char exclvl;	/*Excitation Voltage Level */
> +	bool exca_en;		/* enables EXCA pin as the excitation output */
> +	bool exca_inv_en;	/* enables /EXCA pin as the excitation output */
> +	bool excb_en;		/* enables EXCB pin as the excitation output */
> +	bool excb_inv_en;	/* enables /EXCB pin as the excitation output */
> +};
> +
> +#endif /* IIO_CDC_AD7746_H_ */


^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: [PATCH] iio: adc: Replace, rewrite ad7745 from scratch.
  2011-09-19 12:19 ` Jonathan Cameron
@ 2011-09-19 12:54   ` Jonathan Cameron
  2011-09-19 19:44   ` Hennerich, Michael
  1 sibling, 0 replies; 6+ messages in thread
From: Jonathan Cameron @ 2011-09-19 12:54 UTC (permalink / raw)
  To: Jonathan Cameron
  Cc: michael.hennerich, linux-iio, device-drivers-devel, drivers

On 09/19/11 13:19, Jonathan Cameron wrote:
> 
> One quick nitpick on submission format:
> Please put version in the email subject
> [PATCH V3] iio:...
> 
> That way it's easy to spot which one to bother reading ;)
> 
> On 09/16/11 15:47, michael.hennerich@analog.com wrote:
>> From: Michael Hennerich <michael.hennerich@analog.com>
>>
>> The existing ad7745 driver didn't conform with the IIO spec for such devices.
>> It was way simpler to rewrite the existing driver, than actually fixing it.
>>
>> Changes since V1:
>>
>> Fix file header description.
>> Fix erroneous defines.
>> Pin channels to expected places in the iio_chan_spec array, to avoid magic numbers.
>> Use msleep instead of busy waiting mdelay.
>> Fix indention style.
>> Drop _bias and use _offset attribute.
>>
>> Changes since V2:
>> Increase accuracy of cap scale.
>> Fix channel spec for VIN.
> Some formatting nitpicks. I'll fix them up.
Coccicheck gave me a missaligned code error as well whilst I was doing
final checks...

>> +		case IIO_VOLTAGE:
>> +			if (chan->channel == 1) /* supply_raw*/
>> +				*val = *val * 6;
>> +				break;

Indent wrong above.  Fixed up.

^ permalink raw reply	[flat|nested] 6+ messages in thread

* RE: [PATCH] iio: adc: Replace, rewrite ad7745 from scratch.
  2011-09-19 12:19 ` Jonathan Cameron
  2011-09-19 12:54   ` Jonathan Cameron
@ 2011-09-19 19:44   ` Hennerich, Michael
  2011-09-20  9:15     ` Jonathan Cameron
  1 sibling, 1 reply; 6+ messages in thread
From: Hennerich, Michael @ 2011-09-19 19:44 UTC (permalink / raw)
  To: Jonathan Cameron
  Cc: linux-iio@vger.kernel.org,
	device-drivers-devel@blackfin.uclinux.org, Drivers

Jonathan Cameron wrote on 2011-09-19:
>
> One quick nitpick on submission format:
> Please put version in the email subject
> [PATCH V3] iio:...
>
> That way it's easy to spot which one to bother reading ;)
>
> On 09/16/11 15:47, michael.hennerich@analog.com wrote:
>> From: Michael Hennerich <michael.hennerich@analog.com>
>>
>> The existing ad7745 driver didn't conform with the IIO spec for such
>> devices. It was way simpler to rewrite the existing driver, than
>> actually fixing it.
>>
>> Changes since V1:
>>
>> Fix file header description. Fix erroneous defines. Pin channels to
>> expected places in the iio_chan_spec array, to avoid magic numbers. Use
>> msleep instead of busy waiting mdelay. Fix indention style. Drop _bias
>> and use _offset attribute.
>>
>> Changes since V2:
>> Increase accuracy of cap scale.
>> Fix channel spec for VIN.
> Some formatting nitpicks. I'll fix them up.
>
> I don't think Greg's tree is visible anywhere so I'll pull this through
> mine and push on to him.  Thanks,

Hi Jonathan,

Thanks!
I'm curious, since you own a tree at kernel.org -
Any more precise updates, or rumors when it will go live again?


Greetings,
Michael

--
Analog Devices GmbH      Wilhelm-Wagenfeld-Str. 6      80807 Muenchen
Sitz der Gesellschaft: Muenchen; Registergericht: Muenchen HRB 40368;
Geschaeftsfuehrer:Dr.Carsten Suckrow, Thomas Wessel, William A. Martin, Mar=
garet Seif

^ permalink raw reply	[flat|nested] 6+ messages in thread

* Re: [PATCH] iio: adc: Replace, rewrite ad7745 from scratch.
  2011-09-19 19:44   ` Hennerich, Michael
@ 2011-09-20  9:15     ` Jonathan Cameron
  0 siblings, 0 replies; 6+ messages in thread
From: Jonathan Cameron @ 2011-09-20  9:15 UTC (permalink / raw)
  To: Hennerich, Michael
  Cc: linux-iio@vger.kernel.org,
	device-drivers-devel@blackfin.uclinux.org, Drivers


> 
> Thanks!
> I'm curious, since you own a tree at kernel.org -
> Any more precise updates, or rumors when it will go live again?
> 
Nothing yet.

The users list is now dead as it used forwarding
on hera which is obvious down.  There is a reconstructed
list but only for announcements and none of those since the
front end machines have been down.

Merge window might be interesting.  I wonder if Linus will
hold it up for a while in the hope that kernel.org will
get back online?

Jonathan





^ permalink raw reply	[flat|nested] 6+ messages in thread

end of thread, other threads:[~2011-09-20  9:15 UTC | newest]

Thread overview: 6+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2011-09-16 13:12 [PATCH] iio: adc: Replace, rewrite ad7745 from scratch michael.hennerich
  -- strict thread matches above, loose matches on Subject: below --
2011-09-16 14:47 michael.hennerich
2011-09-19 12:19 ` Jonathan Cameron
2011-09-19 12:54   ` Jonathan Cameron
2011-09-19 19:44   ` Hennerich, Michael
2011-09-20  9:15     ` Jonathan Cameron

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